Raju

Students can access the CBSE Sample Papers for Class 11 Biology with Solutions and marking scheme Term 2 Set 1 will help students in understanding the difficulty level of the exam.

CBSE Sample Papers for Class 11 Biology Term 2 Set 1 with Solutions

Time : 2 Hours
Maximum Marks : 35 

General Instructions:

• All questions are compulsory.
• The question paper has three sections of 23 questions. All questions are compulsory.
• Section-A has 6 questions of 2 marks each; Sedion-B has 6 questions of 3 marks each, and Section-C has a case-based question of 5 marks.
• There is no overall choice. However, internal choices have been provided in some questions. A student has to attempt only one of the alternatives in such questions.
• Wherever necessary, neat and properly labeled diagrams should be drawn.

 

Section – A
(2 Marks each)

Question 1.
Two potted plants were kept in an oxygen-free environment in transparent containers. Plant A was exposed to green light and Plant B to sunlight. Which one of the two, will show more photosynthesis and is likely to survive longer and why?
Answer:
Plant B will show more photosynthesis Chlorophyll absorbs maximum light In the blue region Of the spectrum, i.e., 400-450 nm and hence photosynthetic rate will also be high. Plant A will show negligible amount of photosynthesis or no photosynthesis, as chlorophyll does not absorb any light in the green region, i.e., 500- 550 nm but reflects light.

Question 2.
Different substrates get oxidized during respiration. How does Respiratory Quotient (R.Q.) indicate which type of substrate, i.e., carbohydrate, fat or protein is getting oxidized?
R.Q. = \(\frac{A}{B}\)
What do A and B stand for? What type of substrates have R.Q. of 1, < 1 or > 1?
OR
Energy is released during the oxidation of compounds in respiration. How is this energy stored and released as and when it is needed.
Answer:
In R.Q., A stands for CO₂ released, while B stands for O₂ being consumed by unit mass of a substrate. The ratio indicates the type of substrate being consumed in respiration.

Substance like carbohydrates have RQ = 1, during aerobic respiration.

Proteins and fats have R.Q. of < 1 and are found during germination of seeds.

Substrates like organic acids have R.Q. of > 1 under aerobic conditions.
OR
Energy is stored as bond energy of ATP This bond is broken down to release energy when required.
ADP + Pi + Energy → ADP + Pi or ATP
ATP → ADP + Pi + Energy

Question 3.
Given below is the diagram showing different parts of a stem.

In most of the plants, the terminal bud suppresses the development of lateral buds.

(a) What is this phenomenon called? (1)
(b) Name the phytohormone that can promote the phenomenon. (1)
Answer:
(a) This phenomenon is called Apical dominance.
(b) Auxins are the phytohormones which can promote this phenomenon in plants, e.g., NAA and 2,4-D, etc.

Question 4.
The diagram below shows an ECG of a normal human being. (1)

If a patient’s ECG revealed an abnormally long delay between the P wave and the QRS deflection, what would that suggest?
Answer:
If a patient’s ECG revealed an abnormally long delay between P wave and the QRS deflection, it suggests that there is a delay of conduction from the atria to the ventricles, hence the stimulation from SA nodes are conducting stimuli very slowly to the ventricles.

Question 5.
Sohan was experiencing something abnormal during the urination process. He went to a doctor for a check-up, after which he came to know that his kidneys are damaged. Can you predict what is going to happen to him next?
Answer:
The kidneys are considered as master chemists of the body.

1. If they are damaged, it would disturb the normal functioning of his life processes.
2. Due to the effect of toxins produced by some bacteria, the filters of tiny uriniferous tubules also get damaged.
3. They become perforated with larger holes and allow blood cells, and proteins to pass through them along with the urea and water during filtration of blood in the formation of urine. (Any two)

Question 6.
LH is secreted by Adenohypophysis or anterior pituitary gland. (2)
(a) Mention the other hormone along with which it acts on its target cells/organ. (1)
(b) Give two functions of each hormone. (1)
OR
Study the given diagram.

Why is the above gland referred to as the ‘Master gland’?
Answer:
(a) FSH is the other hormone (gonadotropin) along with which it acts on its target cells/organ.

(b) Functions of LH :

• In males, it stimulates spermatogenesis.
• In females, it stimulates ovulation and formation of the corpus luteum.

Functions of FSH:

• In females, it stimulates the growth of ovarian follicles.
• It regulates the growth and development of secondary sexual characters and other reproductive processes.

OR

1. The given diagram is of the pituitary gland. The pituitary is called “Master Endocrine Gland” because of the number of hormones it produces and the control it exercises over the other endocrine glands.
2. It itself is under the control of the releasing hormones secreted by the hypothalamus of the brain.

Thus, there is a chain of orders : the hypothalamus directs the pituitary output, which controls the secretion of hormones by other endocrine glands.

Section – B
(3 Marks)

Question 7.
(a) Given below is the diagram showing ATP synthesis during aerobic respiration, replace the symbols A, B, C, D and E by appropriate terms given below:
F₁ particle, Pi, 2H⁺, Inner mitochondrial membrane, ATE F₀ particle, ADP (2)

(b) Define the term ETS.
Answer:
(a)

• ATP
• F₁ particle
• Pi
• 2H⁺
• Inner mitochondrial membrane

(b) The metabolic pathway through which the electron passes from one carrier molecule to another is called Electron Transport System (ETS).

Commonly Made Error

• Students often identify incorrect names of the labels.

Answering Tip

• Practice self-explanatory diagrams with proper labelling, arrows and headings.

Question 8.
Japanese farmers in their rice field observed that certain rice seedlings grow excessively tall and become weak and sterile. One of the Japanese plant pathologists found that, it is due to some disease, which is caused by a fungus. He named this disease as “bakane” or “foolish seedling” disease. Yabuta extracted the active substance i.e., growth-promoting substances and termed them as gibberellin.

(a) Name the fungus, which caused “bakane” or “foolish seedling” disease. (1 + ¹/₂)
(b) Give three functions of ‘Gibberellin’. (1 + ¹/₂)

OR

“X” is also called as stress hormone because its synthesis is stimulated by drought, water logging and other adverse environmental conditions. It is produced in many parts of the plants but more abundantly inside the chloroplast of green cells.
(a) Identify “X”. (1)
(b) Mention any two functions of this hormone. (1)
(c) How are they antagonistic to gibberellins? (1)
Answer:
(a) Gibberella fujikuroi is the fungus which causes ‘Bakane’ or foolish-seedling disease. Gibberellin, a plant hormone was discovered from the same fungus.

(b) The functions of Gibberellins are :

• Bolting and flowering.
• Stem elongation and fruit ripening.
• Parthenocarpy.
• Early seed production. (Any three)

Commonly Made Error

• Some students get confused between the functions of different hormones.

Answering Tip

• Students should learn the functions of phytohormones or plant hormones thoroughly. They should make a flow chart to learn the functions separately.

OR
(a) The hormone “X” is Abscisic add.
(b) Functions of Absdsic acid:

(i) Abscisic acid owes its name to its role in the abscission of plant leaves. In preparation for winter, ABA is produced in terminal buds. This slows plant growth and directs leaf primordia ‘ to develop scales to protect the dormant buds during the cold season.

(ii) It plays an important role in seed development and maturation.

(c) They are antagonistic to gibberellins as gibberellin promotes stem elongation while absdsic add acts as plant growth inhibitor.

Question 9.
The diagram given below represents a section of human heart.

(a) Which parts of the heart are in the diastolic phase? Give a reason to support your answer. (1)
(b) Label the parts numbered 1 and 2 in the diagram. What type of blood flows through them. (1)
(c) What causes the heart sounds ‘LUBB’ and ‘DUBB’. (1)
Answer:
(a) Ventricles
As Tricuspid and bicuspid valves are open/ Semilunar valves are closed.

(b) 1 – Pulmonary artery, deoxygenated blood.
2 – Pulmonary veins, oxygenated blood.

(c) LUBB – Closure of tricuspid and bicuspid valves.
DUBB – Closure of semilunar valves.

Commonly Made Error

• Students often identify the parts of the heart in diastolic phase but many of them fail to give a reason to support the answer.

Answering Tip

• Carefully learn each and every part of the heart together with their functions.

Question 10.
(a) How is glomerular filtrate hypertonic and hypotonic in descending and ascending limb of loop of Henle respectively? (1 + ¹/₂)
(b) What is the effect of ADH on collecting tubules? (1 + ¹/₂)
Answer:
(a) Counter-current system is found in two limbs of loop of Henle. The ascending limb transports Na+ and some urea into surrounding medullary tissue. It is impermeable to water. So, it makes urine dilute or hypotonic. The walls of descending limbs are permeable to water and salt, so Na+ and water from the surrounding fluid are absorbed. Thus, the contents of urine become hypertonic.

(b) ADH (Antidiuretic Hormone): ADH is secreted when the osmotic pressure of blood increases due to excess loss of water from the body. The hormone renders the walls of the distal convoluted tubule (DCT), collecting tubule (CT) and collecting duct of a nephron permeable to water and increases the reabsorption of water into the surrounding tissues and particular capillaries.

The urine becomes hyperosmotic and less in volume and water is conserved in the body.

Commonly Made Error

• Students generally get confused between hypertonic and hypotonic terms and write incorrect answer. Students also write incorrect permeability of descending and ascending limbs of loop of Henle.

Answering Tip

• Students should understand the terms/concepts clearly, instead of rote learning.

Question 11.
The given diagram represents the structure of a human brain.

(a) Identify the label A, B and C. (1 + ¹/₂)
(b) What happens if medulla oblongata is damaged due to some accident? (1)
(c) State any one function of cerebellum. (¹/₂)
Answer:
(a) In the given structure of brain, the label A represents the cerebrum, Label B is cerebellum, and label C is brain stem.

(b) Medulla oblongata is a part of brain stem, derived from the hindbrain that is continuous with the spinal cord. Its function is a to regulate the reflex responses controlling respiration, heartbeat, blood pressure, and other involuntary processes. So, if medulla oblongata gets damaged, it can lead to respiratory failure, paralysis, or loss of sensation.

(c) Cerebellum maintains equilibrium and posture.

Question 12.
A patient was complaining of frequent urination, excessive thirst, hunger and tiredness. His fasting blood was found higher than 130 mg/dL on two occasions.
(a) Name the disease. (1)
(b) Give the root cause of this disease. (1)
(c) Explain why the blood glucose level is higher than 130 mg/dL. (1)
Answer:
(a) The disease is Diabetes mellitus.
(b) The failure of the p-cells of the islets of Langerhans of pancreas to produce an adequate amount of insulin, is the root cause of this disease.
(c) It was due to the under secretion of insulin hormone. The under secretion of insulin impairs the following functions:

• Utilisation and uptake of glucose by adipocytes and hepatocytes.
• Conversion of glucose into glycogen by the above target cells.

Section – C
(5 Marks)

Question 13.
Mitosis is the process of cell division in which one cell gives rise to two genetically identical daughter cells, resulting in cell duplication and reproduction. The major purpose of mitosis is for growth and to replace worn out cells., It is divided into four phases, namely, prophase, metaphase, anaphase and telophase.

(a) Why is mitosis an equational division? (1)
(b) What would be the consequences if each of the following irregularities occurs during mitosis?
(i) Nuclear membrane fails to disintegrate. (1)
(ii) Duplication of DNA does not occur. (1)
(iii) Centromeres do not divide. (1)
(iv) Cytokinesis does not occur. (1)
OR
In a biology class, teacher explains the students, the different stages of cell cycle. She has drawn a diagram that explains the events taking place during cell cycle of a somatic cell.

(a) What is G₁ phase in the cell cycle? (2)
(b) What amount of DNA is present in the cell during the G₂ phase? (1)
(c) How does cytokinesis differ in plant and animal cells? (2)
Answer:
(a) Mitosis is an equational division because the daughter cells have the same number of chromosomes and an equal amount of cytoplasm.

(b)

1. If nuclear membrane fails to disintegrate, the spindle fibers would not be able to reach chromosomes and they would not move towards opposite poles of the cell.
2. If duplication of DNA does not occur, then the cell might not be able to surpass S phase of the cell cycle. Thus, the cell will not be able to enter M-phase or if in case it enters mitosis, the cycle will cease.
3. If centromeres do not divide, then the daughter cell will receive a complete pair of chromosomes. This may result in trisomy.
4. If cytokinesis does not occur, then it would not result in the formation of daughter cells.

OR

(a) Gj phase:

• In this phase, the cell is metabolically active and continuously grows but does not replicate its DNA.
• RNA and proteins are synthesized and the cell grows in size.

(b) Double the amount of DNA present in the original diploid cell.
(c) Differences between cytokinesis in plant cells and animal cells:

Cytokinesis in plant cells	Cytokinesis in animals cells
In these, cell wall formation starts at the centre of the cell and grows outward to meet the existing lateral walls.	In these cells, cytokinesis is achieved by the appearance of a furrow in the plasma membrane.
Formation of new cell wall begins with the formation of a precursor called cell plate.	The furrow gradually deepens and ultimately join in the centre dividing the cytoplasm into two.

Students can access the CBSE Sample Papers for Class 11 Chemistry with Solutions and marking scheme Term 2 Set 4 will help students in understanding the difficulty level of the exam.

CBSE Sample Papers for Class 11 Chemistry Standard Term 2 Set 4 for Practice

Max. Marks: 40
Time: 2 Hours
General Instructions:
Read the following instructions carefully.

• There are 12 questions in this question paper with internal choice.
• SECTION A-Q. No. 1 to 3 are very short answer questions carrying 2 marks each.
• SECTION B-Q. No. 4 to 11 are short answer questions carrying 3 marks each.
• SECTION C-Q. No. 12 is case based question carrying 5 marks.
• Alt questions are compulsory.
• Use of log tables and calculators is not allowed.

Section – A (2 Marks each)

Question 1.
Arrange the following in the increasing order of their property indicated (any 2):
(j) BaCl₂, MgCl₂, BeCl₂, CaCl₂ (ionic character)
(ii) Mg(OH)₂, Sr(OH)₂, Ba(OH)₂, Ca(OH)₂ (Increasing solubility in water)
(iii) MgCO₃,CaCO₃, SrCO₃ and BaCO₃ (thermal stability)

Question 2.
In one litre saturated solution of AgCl [K_sp = 1.6 × 10^-10 0.1 mol of CuCl [K_sp = 1.0 × 10⁶] is added. Find out the resultant concentration of Ag⁺ in the solution.

Question 3.
Give reasons to support your answer:
(i) Although heat is a path function but heat absorbed by the system under certain specific conditions
is independent of path.
(ii) Density, pressure and temperature are intensive properties.

Section – B (3 Marks each)

Question 4.
Account for the following:
(i) The boiling point of pentane is higher than 2,2-dimethylpropane.
(ii) Acetylene is acidic but it does not react with NaOH or KOH.
(iii) AIkynes do not show geometrical isomerism.
OR
Convert the following:
(i) Ethyne into but-2-yne
(ii) Acetic acid into methane,
(iv) Bromoethane into ethane.

Question 5.
Answer the following questions:
(i) Silicon forms \(\mathrm{SiF}_{6}^{2-}\) ion whereas corresponding fluoro compound of carbon is not known. Explain to support your answer.
(ii) What is the state of hybridisation of carbon in (a) \(\mathrm{CO}_{3}^{2}\), (b) Diamond
OR
(i) Why CCl₄ is immiscible in water whereas SiCl₄ is easily hydrolysed?
(ii) Write balanced equations for:
(a) BF₃ + LiH →
(b) A1 + NaOH →

Question 6.
Account for the following:
(i) Down the group, stability of peroxide and superoxide of alkali metals increases.
(ii) LiF is almost insoluble in water whereas LiCl is soluble not only in water but also in acetone.
(iii) Alkali metals are prepared by electrolysis of their fused chlorides.

Question 7.
An alkene A’ contains three C – C, eight C – H σ bonds and one C – C π bond. ‘A’ on ozonolysis gives two moles of an aldehyde of molar mass 44 u. Write IUPAC name of A.

Question 8.
Observe the figure given below and answer the questions that follow:
The variation of pressure with volume of the gas at different temperatures can be graphically represented as shown in figure.

(i) An increase in pressure of a gas at constant temperature, how does the volume of gas vary?
(ii) What will be the change in volume of gas observed if the temperature is increased from 200K to
400K at a constant pressure?
(iil)Calculate the volume occupied by 8.8 g of carbon dioxide at 31.1°C and I bar pressure. (R = 0.083
bar L K^-1 mol^-1]

Question 9.
What happens when the following chemical reactions occur:
(i) Beniene is treated with acetyl chloride in presence of anhydrous AlCl₃
(ii) Sodium acetate solution is electrolysed.
(ili)Hexane on heating with vanadium oxide over alumina at 10-20 atm pressure.
OR
(i) Write IUPAC names of the following organic compound:

(ii) Complete the following chemical reaction:

Question 10.
What will be the pressure of the gas mixture when 0.5L of H₂ at 0.8 bar and 2.0L of oxygen at 0.7 bar
are introduced in a 1L vessel at 27°C?

Question 11.
(i) Why BCl₃ molecule has zero dipole moment, while B-Cl bond has a dipole moment?
(ii) Why pπ – pπ bonding occur in halides of boron and not in those of aluminium?
(iii) What is the resonance structures of CO₃^2- and HCO₃^–.
OR
On the basis of the figure given below, answer the following questions:

(i) Why do BCl₃ and AlCl₃ behave as Lewis acids?
(ii) BCl₃ exists as monomer whereas AlCl₃ is dimerised. Why?
(iii) When BCl₃ is treated with water, it hydrolysis and forms [B(OH)₄]^– only whereas, AlCl₃ in acidified
aqueous solution forms [Al(H₂O)₆]³⁺ Explain what is the hybridisation of boron and aluminium in
these species?

Section – C (5 Marks )

Question 12.
Read the passage given below and answer the questions that follow.
The theory of thermodynamics can be summarised in its three main laws. The zeroth law introduces the notion of thermal equilibrium as an equivalence relation of states, where temperature is the parameter that labels the different equivalence classes. In particular, the transitive property of the equivalence relation implies that if a body A is in equilibrium with a body B, and B is with a third body C, then A and C are also in equilibrium. The first law assures energy conservation. It states that in a thermodynamic process not all of energy changes are of the same nature and distinguishes between work, the type of energy that allows for “useful” operations as raising a weight, and its complement heat, any energy change which is not work.

Finally, the second law establishes an arrow of time. It has several formulations and perhaps the most common one is the Clausius statement, which states that no process is possible whose sole result is the transfer of heat from a cooler to a hotter body. Such a restriction not only introduces the fundamental limit on how and to what extent various forms of energy can be converted to accessible mechanical work, but also implies the existence of an additional state function, the entropy, which has to increase.
(i) Name the system which can neither exchange matter nor energy with the surroundings.
(ii) What is the significance of Zeroth Law?
(iii) What Will be the sign of AS for the following reaction? Why is it so?
N₂(g) + O₂(g) → 2NO(g)
(iv) The enthalpy of combustion of methane, graphite and dihydrogen at 298 K are – 890.3 kj mol^-1, -393.5 kj mol^-1 and -285.8 kj mol^-1 respectively. What is the enthalpy of formation of CH₄?
OR
1 g of graphite is burnt in a bomb calorimeter in excess of oxygen at 298 K and 1 atmospheric pressure according to the equation:
C (graphite) + O₂(g) → CO₂(g)
During the reaction, temperature rises from 298K to 299K. If the heat capacity of the bomb calorimeter is 20.7 kJ/K. What is the enthalpy change for the above reaction at 298K and 1 atm?

Students can access the CBSE Sample Papers for Class 11 Chemistry with Solutions and marking scheme Term 2 Set 5 will help students in understanding the difficulty level of the exam.

CBSE Sample Papers for Class 11 Chemistry Standard Term 2 Set 5 for Practice

Max. Marks: 40
Time: 2 Hours
General Instructions:
Read the following instructions carefully.

• There are 12 questions in this question paper with internal choice.
• SECTION A-Q. No. 1 to 3 are very short answer questions carrying 2 marks each.
• SECTION B-Q. No. 4 to 11 are short answer questions carrying 3 marks each.
• SECTION C-Q. No. 12 is case based question carrying 5 marks.
• Alt questions are compulsory.
• Use of log tables and calculators is not allowed.

Section – A (2 Marks each)

Question 1.
Arrange the following in the increasing order of their property indicated (Any 2):
(i) Tin, Silicon, Germanium,Carbon (Catenation)
(ii) Aluminium, Gallium, Boron, Thallium, Indium (Ionisation enthalpy)
(iii) Carbon, Tin, Germanium, Silicon (Electronegativity)

Question 2.
What are allotropes? What is the impact of structure on physical properties of two allotropes?

Question 3.
Give reasons to support your answer:
(i) Lithium forms only monoxide where as sodium forms peroxide. Why?
(ii) Second ionisation energy of group 2 elements is less than group 1 elements.

Section – B (3 Marks each)

Question 4.
Account for the following:
(i) For an electruphilic substitution reaction, the presence of a halogen atom in the benzene ring affect
reaction.
(ii) An alkene A on ozonolysis gives a mixture of ethanal and pentan-3- one.
(iii)In an electrophiic substitution reaction of nitrobenzene, the presence of nitro group affect the
reaction.
OR
Convert the following:
(i) Benzene into ethylbenzene
(ii) Phenol into Benzene
(iv) Propyne into propane

Question 5.
Answer the following questions: IBS
(i) The pressure of a 1:4 mixture of dihydrogen and dioxygen enclosed in a vessel is one atmosphere. What would be the partial pressure of dioxygen?
(ii) Which are the two wrong assumptions of the kinetic molecular theory of gases which led to the failure of the ideal gas law?
OR
(i) A vessel of 120 ml capacity contains a certain amount at 35°C and 1.2 bar pressure. The gas is transferred to another vessel of volume 180 mL at 35°C. What would be its pressure ?
(ii) Compressibility factor, Z, of a gas is given as Z = \(\frac{\mathrm{PV}}{n \mathrm{RT}}\)
(a) What is the value of Z for an ideal gas ?
(b) For real gas what will be the effect on the value of Z above Boyle’s temperature ?

Question 6.
Account for the following:
(i) Why is the standard enthalpy of formation of diamond not zero although it is an element?
(ii) Why entropy of steam is more than that of water at its boiling point?
(iii) One mole of acetone requires less heat to vaporise than 1 mole of water.

Question 7.
An unsaturated hydrocarbon ‘A’ adds two molecules of H₂ and on reductive ozonolysis gives butane-1,4- dial, ethanal and propanone. Give the structure of ‘A’, write its IUPAC name and explain the reactions involved.

Question 8.
Observe the figure given below and answer the questions that follow:

(i) What does the diagram in the figure used for?
(ii) Derive relationship between ΔH and ΔU.
(iii) Internal energy of a system belongs to which type of property?

Question 9.
What happens when reactions:
(i) m-xylene is treated with Br₂ in presence of FeBr3.
(ii) Acetylene is passed through dil. H₂SO₄ in presence of HgSO₄.
(iii) Propene on reaction with Bayer’s reagent.
OR
(i) Write IUPAC names of the following:

(ii) Complete the following:

Question 10.
An organic base X has K equal to 1 × 10^-8. In what amount should 0.01 M HCl and 0.01 M solution of X be mixed to prepare 1 litre of a buffer solution having pH = 7?

Question 11.
(i) For the reaction, the standard free energy is ΔG°> 0. What is the value
of K?
(ii) A solution of Na₂CO₃ is alkaline. Given reason.
(iii) Ba(OH)₂ is soluble in water while BaSO₄ is almost insoluble. Given reason.
OR
On the basis of the figure given below, answer the following questions:

(i) In which of the figure, forward reaction is favoured?
(ii) What does it tell about the (heat produced/absorbed in the reaction) type of reaction?
(iii) An equilibrium mixture at 300 K contains N₂O₄ and NO₂ at 0.28 and 1.1 atmospheric pressures respectively. If the volume of the container is doubled, calculate the new equilibrium pressure of the two gases.

Section – C (5 Marks)

Question 12.
Read the passage given below and answer the questions that follow:
The alkaline earth metals have low ionization enthalpies due to fairly large size of the atoms. Since, the atomic size increases down the group, their ionization decreases. The first ionization enthalpies of the alkaline earth metals are higher than those of the corresponding group 1 metals. This is due to their small size as compared to the corresponding alkali metals. The second ionization enthalpies of the alkaline earth metals are smaller than those of the corresponding alkali metals.

(i) Why do alkaline earth metals act as reducing agents?
(ii) Why the second ionization enthalpies of the alkaline earth metals are smaller than the alkali metals?
(iii) Why do Be and Mg not impart colour to the flame?
(iv) Name an element from group 2 which forms an amphoteric oxide and a water soluble sulphate.
OR
Mention two properties of lithium which are similar to magnesium.

Students can access the CBSE Sample Papers for Class 11 Economics Education with Solutions and marking scheme Term 2 Set 5 will help students in understanding the difficulty level of the exam.

CBSE Sample Papers for Class 11 Economics Term 2 Set 5 with Solutions

Time : 2 Hours
Maximum Marks : 40

General Instructions:

• This is a subjective question paper containing 13 questions.
• This paper contains 5 questions of 2 marks each, 5 questions of 3 marks each and 3 questions of 5 marks each.
• Section A, 2 marks questions are Short Answer Type Questions-Answer them in 30-50 words.
• Section B, 3 marks questions are Short Answer Type Questions-Answer them in 50-80 words.
• Section C, 5 marks questions are Long Answer Type Questions-Answer them in 80-120 words.
• This question paper contains Case/Source Based Questions.

Section – A
(2 Marks Each)

Question 1.
Explain any two causes of “Decrease” in the supply of a commodity. (2)
OR
Explain the distinction between ‘change in supply’ and ‘change in quantity supplied.’ (2)

Question 2.
Using the simple aggregative method, calculate the index number for the given data. (2)

Commodity	A	B	C	D
P1	15	22	20	27
p0	10	20	18	25

Question 3.
Why does the government of India fix ‘support price’ for some crops? Explain. (2)

Question 4.
List the merits of Standard Deviation. (2)
OR
Write down any two characteristics of a good measure of dispersion. (2)

Question 5.
What are the effects of ‘price-floor’ (minimum price ceiling) on the market of a good? Use diagram. (2)
OR
Explain the implications of the “freedom of entry and exit” feature of perfect competition.

Section – B
(3 Marks Each)

Question 6.
Can the CPI number for urban non-manual employees represent the changes in the cost of living of the President of India? (3)
OR
Why do we need an index number?

Question 7.
Calculate Price Elasticity of Supply from the following data: (3)

Price Per Unit (₹)	10	12
Total Revenue (₹)	2000	2400

Read the following passage and answer Q.8 and Q.9 that follows:

Competition degrees means the power or the influence that a firm creates over the market which eventually affects the whole structure and thus the system works according to the competition.

Perfect competition, which means that there are a large number of sellers in the market who compete for the customers.

Monopolistic competition, is the type of competition in which there are many sellers who produce quite similar products, but the customers see their products as differently, which creates the competition.

The third is Oligopoly, where few firms compete or collaborate with each other.

The fourth is the Monopoly, which means a single seller selling unique project.

Question 8.
Explain the implication of large number of sellers under perfect competition. (3)

Question 9.
Explain tire implication of’one seller’feature of monopoly. (3)

Question 10.
Define Revenue. State the relation between marginal revenue and average revenue. (3)

Section – C
(5 Marks Each)

Question 11.
Calculate Karl Pearson’s coefficient of correlation with the help of following data:

x	6	8	12	15	18	20	24	28	31
y	10	12	15	15	18	25	22	26	28

Question 12.
(i) Why is total variable cost curve inverse S-shaped? (2)
(ii) What is Average Fixed Cost of a firm? Why is an Average Fixed Cost Curve a Rectangular Hyperbola? Explain with help of a diagram. (3).

Question 13.
Calculate Coefficient of Variation from the following data: (5)

Number of Goals Scored	0	1	2	3	4
Number of Matches Played	27	9	8	5	4

OR
(a) The following data shows the daily wages for 199 workers in a factory. Find out quartile deviation and coefficient of quartile deviation for the following data: (2)

Wages (₹)	10	20	30	40	50	60	70	80	90	100
Number of Workers	2	8	20	35	42	20	28	26	16	2

(b) List any five characteristics of an ideal measure of dispersion. (3)

Students can access the CBSE Sample Papers for Class 11 Physics with Solutions and marking scheme Term 2 Set 5 will help students in understanding the difficulty level of the exam.

CBSE Sample Papers for Class 11 Physics Standard Term 2 Set 5 for Practice

Time Allowed: 2 Hours
Maximum Marks: 40

General Instructions:

• There are 12 questions in all. All questions are compulsory.
• This question paper has three sections: Section A, Section B and Section C.
• Section A contains three questions of two marks each, Section B contains eight questions of three marks each, Section C contains one case study-based question of five marks.
• There is no overall choice. However, an internal choice has been provided in one question of two marks and two questions of three marks. You have to attempt only one of the choices in such questions.
• You may use log tables if necessary but use of calculator is not allowed.

Section – A (2 Marks Each)

Question 1.
Why does an iron needle float on clean water but sink when some detergent is added to this water?

Question 2.
Is it possible to increase the temperature of a gas without adding heat to it? If yes, then explain how?
OR
Why does specific heat of gases increase with their atomicity ?

Question 3.
Which is more elastic: steel or rubber? Give reason.

Section – B (3 Marks Each)

Question 4.
Prove that C_P is greater than C_V.

Question 5.
A particle moving in a straight line has velocity υ given by υ² = α – βy² , where a and β are constant and y is its distance from a fixed point in the line. Show that the motion of the particle is S.H.M. Find its time period and amplitude.

Question 6.
Derive Charles’s law on the basis of kinetic theory of gases.

Question 7.
(i) Are all periodic functions simple harmonic motion? Give reason for your answer.
(ii) A simple pendulum performs S.H.M. about x = 0 with an amplitude a and time period T. What is the speed of the pendulum at x = a/21

Question 8.
Derive an expression for work done in isothermal process.
OR
A hydraulic automobile lift is designed to lift cars with a maximum mass of 3000 kg. The area of cross-section of the piston carrying the load is 425 cm². What maximum pressure would the smaller piston have to bear?

Question 9.
What is the value of elasticity for
(a) Young’s modulus
(b) Bulk modulus

Question 10.
Derive an expression for fundamental frequency and various overtones of a closed pipe open at one end.

Question 11.
A set of 24 tunning forks is arranged in order of decreasing frequency. Each fork gives 4 beats with succeeding one. The first fork is octave of the last. Calculate the frequency of the first and 12^th fork.
OR
Giving reasons for your selection, select pairs out of the following four waves in a medium which will give rise to (i) beats, (ii) destructive interference, (iii) stationary waves.
1. ξ₁ = Acos 2π(υ₁t + \(\frac{x}{\lambda_{1}}\))
2. ξ₂ = Acos 2π(υ₁t + \(\frac{x}{\lambda_{1}}\) + π)
3. ξ₃ = Acos 2π(υ₁t + \(\frac{x}{\lambda_{2}}\))
4. ξ₄ = Acos 2π(υ₁t + \(\frac{x}{\lambda_{2}}\))

Section – C (5 Marks)

Question 12.
CASE STUDY: PROPERTIES OF AN IDEAL GAS
A cubic vessel ABCDEFGH (with faces horizontal + vertical) contains an ideal gas at NTE The vessel
is being carried by a rocket which is moving up at a speed of 500 ms.
(i) The pressure of the gas inside the vessel as observed by us on the ground
(a) remains the same because 500 ms^-1 is very much smaller than v_rms of the gas.
(b) remains the same because motion of the vessel does not effect the relative motion of the gas
molecules and the walls.
(c) will increase by a factor equal to(υ²_rms + (500)²)/υ²_rms where υ_rms was the original mean square velocity of the gas
(d) will be different on the top and bottom wall of the vessel.

(ii) If the face of cube (EFGH) is made up of a material any gas molecule incident on it. At any given time,

(a) pressure on EFGH would be zero.
(b) pressure on all the faces will the equal.
(c) pressure of EFGH =2(Pressure on ABCD)
(d) pressure of EFGH = 1/2 (Pressure on ABCD)

(iii) Gas laws are applicable for ideal gas. Boyle’s law is applicable for an
(a) adiabatic process
(b) isothermal process.
(c) isobaric process
(d) isochoric process.

(iv) Volume versus temperature graphs for a given mass of an ideal gas are shown at two different values of constant pressure. What can be inferred about relation between P₁ and P₂?

(a) P₁ > P₂
(b) P₁ = P₂
(c) P₁ < ₂
(d) data is insufficient

(v) If the top surface of cube is replaced with frictionless movable piston of mass M, then as temperature is increased,

(a) both P and V of the gas will change.
(b) only P will increase according to Charles’s law.
(c) V will change but not P
(d) P will change but not V.

Students can access the CBSE Sample Papers for Class 11 Economics Education with Solutions and marking scheme Term 2 Set 4 will help students in understanding the difficulty level of the exam.

CBSE Sample Papers for Class 11 Economics Term 2 Set 4 with Solutions

Time : 2 Hours
Maximum Marks : 40

General Instructions:

• This is a subjective question paper containing 13 questions.
• This paper contains 5 questions of 2 marks each, 5 questions of 3 marks each and 3 questions of 5 marks each.
• Section A, 2 marks questions are Short Answer Type Questions-Answer them in 30-50 words.
• Section B, 3 marks questions are Short Answer Type Questions-Answer them in 50-80 words.
• Section C, 5 marks questions are Long Answer Type Questions-Answer them in 80-120 words.
• This question paper contains Case/Source Based Questions.

Section – A
(2 Marks Each)

Question 1.
The sum of 100 values is 1,000 and the sum of their square is 10,900. Find the coefficient of variation. (2)
The price of an article which was ₹150 in 2005 increased to ₹300 in 2007. The increase in 2007 on the base year 2005 was 100%. So using 2007 as base year, what should have been the decrease in 2005?

Question 2.
If the points in a scatter diagram tend to cluster in a straight line which makes an angle of 30° with the X-axis, what would you say about the strength of association between X and Y? (2)

Question 3.
Draw Total Variable Cost, Total Cost and Total Fixed Cost curves in a single diagram. (2)
OR
Price elasticity of supply of a commodity is 1. Its price rises from f 20 to ₹24 per unit and its supply rises by 300 units. Calculate its supply at the original price of ₹20 per unit. (2)

Question 4.
What is the Law of Diminishing Marginal Returns? (2)

Question 5.
Why is the total revenue curve of a price-taking firm an upward-sloping straight line? Why does the curve pass through the origin? (2)
OR
Explain the implications of the feature “homogeneous product” in a perfectly competitive market. (2)

Section – B
(3 Marks Each)

Question 6.
If the salary of a person in the base year is ₹4,000 per annum and the current year salary is ₹6,000, by how much should his salary rise to maintain the same standard of living if the CPI is 400? (3)

Question 7.
Explain the relationship between TR, AR and MR with the help of a table. (3)
OR
Comment on the shape of the MR curve in case the TR curve is a:

(i) Positively sloped straight line passing through the origin.
(ii) Horizontal line.

Read the hypothetical case study and answer the Q. 8 and Q. 9 that follows:

Law of Supply states that, other things being equal, quantity supplied increases with increase in price and decreases with decrease in price of a commodity.

Assumptions of Law of Supply: The Law of Supply assumes the following as constant:
(i) Price of all related goods
(ii) Prices of input of factors of production
(iii) Technique of production
(iv) Goals of the producer
(v) Policies of the government
(vi) Expectations about the market

Exceptions to the Law of Supply:
Agricultural Produce: The supply of agricultural produce cannot be increased with increase in prices because of limitation of agricultural land and the time involved in producing a fresh crop. Also, it is more season dependent. On the other hand, most of the agricultural produce like fruits and vegetables is perishable in nature. This is why, their supply cannot be reduced with decrease in prices.

Supply of Labour: The supply of labour is an exception to the law of supply. Initially, the supply of labour follows the law of supply, that is, with an increase in wage rate, there is an increase in supply of labour. But beyond a certain wage rate, the labour prefers to have some relaxed hours. The workers can maintain the same standard of living by working for fewer hours at higher wage rates. As a result, beyond that wage rate, the supply of labour starts falling. As a result, the supply curve of labour is backward bending.

Question 8.
Explain how changes in prices of other products influence the supply of a given product. (3)

Question 9.
The agricultural produce and the labour supply are the exceptions to the supply curve as they do not have an upward rising supply curve, but when the assumption of law of supply is not working it may result in the rightward shift or the leftward shift in the supply curve. State three reasons which can cause it. (3)

Question 10.
Explain the effects of ‘maximum price ceiling’ on the market of a good. Use diagram. (3)

Section – C
(5 Marks Each)

Question 11.
Construct Index Number of price of 2011 from the following data by:
(i) Laspeyre’s Method
(ii) Paasche’s Method
(iii) Fisher’s Method

Commodity	2001		2011
	Price	Quantity	Price	Quantity
A	15	40	22	45
B	18	18	21	12
C	28	20	30	25
D	16	25	17	30

Question 12.
Calculate Standard Deviation for the following distribution. (5)

Class	Frequencies
20-40	3
40-80	6
80-100	20
100-120	12
120-140	9
	50

Question 13.
Giving reasons, state whether the following statements are true or false:
(i) When the equilibrium price of a good is less than the market price, there will be competition among the sellers.
Excess supply of a commodity exists when its market price is greater than its equilibrium price. [2 ¹/₂ × 2]
OR
Suppose the value of demand and supply curves of a Commodity-X is given by the following two equations simultaneously:
Q_d – 200 – 10p
Q_s = 50 + 15p
(i) Find the equilibrium price and equilibrium quantity of commodity X.
(ii) Suppose that the price of a factor input used in producing the commodity has changed, resulting in the new supply curve given by the equation:
Q_s – 100 + 15p

Analyse the new equilibrium price and new equilibrium quantity as against the original equilibrium price and equilibrium quantity. (5)

Students can access the CBSE Sample Papers for Class 11 Physics with Solutions and marking scheme Term 2 Set 4 will help students in understanding the difficulty level of the exam.

CBSE Sample Papers for Class 11 Physics Standard Term 2 Set 4 for Practice

Time Allowed: 2 Hours
Maximum Marks: 40

General Instructions:

• There are 12 questions in all. All questions are compulsory.
• This question paper has three sections: Section A, Section B and Section C.
• Section A contains three questions of two marks each, Section B contains eight questions of three marks each, Section C contains one case study-based question of five marks.
• There is no overall choice. However, an internal choice has been provided in one question of two marks and two questions of three marks. You have to attempt only one of the choices in such questions.
• You may use log tables if necessary but use of calculator is not allowed.

Section – A (2 Marks Each)

Question 1.
The excess pressure inside a soap bubble is thrice the excess pressure inside a ’second soap bubble. What is the ratio of volume of two bubbles ?

Question 2.
Why a thick glass tumbler cracks when boiling water is poured in it ?
OR
An alloy consist of n metals of masses m₁ m₂ m₃ …, m_n and specific heat capacities c₁ c₂, c₃ …c_n. If the specific heat capacity of alloy is c, then calculate c.

Question 3.
What is an ‘Indicator diagram’ ? What is its importance ?

Section – B (3 Marks Each)

Question 4.
Define the coefficient of thermal conductivity.

Question 5.
Consider a cycle tyre being filled with air by a pump. Let V be the volume of the tyre (fixed) and at each stroke of the pump ΔV(« V) of air is transferred to the tube adiabatically. What is the work done when the pressure in the tube is increased from P₁ to P₂ ?

Question 6.
Calculate the average kinetic energy for one molecule of a gas at constant volume.

Question 7.
The periodic time of a mass suspended by a spring (force constant k) is T If the spring is cut in three equal pieces, what will be the force constant of each part? If the same mass be suspended from one piece, what will be the periodic time?

Question 8.
By using Stokes law, derive an expression for terminal velocity. On what factors does it depend ?
OR
An air bubble of radius r rises steadily through a liquid of density p at the rate of v. Neglecting density of air, find the coefficient of viscosity of liquid.

Question 9.
A particle in linear simple harmonic motion has a velocity of 4 ms^-1 at 3 m at 3 ms^-1 at 4 m from mean position. What is the time taken to travel half the amplitude from its positive extreme position ?

Question 10.
The wave pattern on a stretched string is shown in Fig. Interpret what kind of wave this is and find
its wavelength.

Question 11.
A steel wire has a length of 12 m and a mass of 2.10 kg. What will be the speed of a transverse wave on this wire when a tension of 2.06 × 10⁴ N is applied?
OR
List the factors affecting the speed of sound in a gaseous medium.

Section – C (5 Marks)

Question 12.
Case Study: Sagging of a bridge
A bridge is designed such that it can withstand the load of the flowing traffic, the force of winds and its own weight.

Let us consider the case of a beam loaded at the centre and supported near its ends as shown in Figure.
A beam of length l, breadth b, and depth d when loaded at the centre by a load W sags by an amount given by
δ = \(\frac{W l^{3}}{4 b d^{3} Y}\)

From the equation, we see that to reduce the bending for a given load, one should use a material with a large Young’s modulus Y. For a given material, increasing the depth d rather than the breadth b is more effective in reducing the bending, since 8 is proportional to d^-3 and to b^-1 (of course the length l of the span should be as small as possible).

Amongst bridge materials, steel has the highest and most favorable strength qualities, and it is therefore suitable for the most daring bridges with the longest spans. Normal building steel has compressive and tensile strengths of 370 N/sq. mm, about ten times the compressive strength of a medium concrete and a hundred times its tensile strength. A special merit of steel is its ductility due to which it deforms considerably before it breaks, because it begins to yield above a certain stress level.
(i) To reduce bending of a beam
(a) For a given length and material, depth should be greater than breadth.
(b) For a given length and material, breadth should be greater than depth.
(c) For a given length and material, depth should be equal to breadth.
(d) Breadth and depth has no effect. [1]

(ii) Compressive strength of normal building steel is about ………………….. times of the compressive strength of medium concrete.
(a) 2
(b) 10
(c) 100
(d) 1000 [1]

(iii) What is the special merit of steel over concrete is its
(a) Malleability
(b) Brittleness
(c) Conductivity
(d) Ductility [1]

(iv) A bar of length l, breadth b, and depth d, supported at two ends when loaded at the centre by a load W sags by an amount given by
(a) δ = \(\frac{W l^{3}}{4 b d^{3} \mathrm{Y}}\)
(b) δ = \(\frac{W l}{4 b d^{3} \mathrm{Y}}\)
(c) δ = \(\frac{W l^{3}}{4 b^{3} d Y}\)
(d) δ = \(\frac{W Y l^{3}}{4 b d^{3}}\)

(v) Why ductility is the special merit of steel?
(a) Ductility allows structures to bend and deform to some extent without rupturing.
(b) Ductility offers the structure a high rigidity
(c) Ductility prevents the structure to sag while overloaded
(d) Ductility offers less corrosion

Students can access the CBSE Sample Papers for Class 11 Economics Education with Solutions and marking scheme Term 2 Set 3 will help students in understanding the difficulty level of the exam.

CBSE Sample Papers for Class 11 Economics Term 2 Set 3 with Solutions

Time : 2 Hours
Maximum Marks : 40

General Instructions:

• This is a subjective question paper containing 13 questions.
• This paper contains 5 questions of 2 marks each, 5 questions of 3 marks each and 3 questions of 5 marks each.
• Section A, 2 marks questions are Short Answer Type Questions-Answer them in 30-50 words.
• Section B, 3 marks questions are Short Answer Type Questions-Answer them in 50-80 words.
• Section C, 5 marks questions are Long Answer Type Questions-Answer them in 80-120 words.
• This question paper contains Case/Source Based Questions.

Section – A
(2 Marks)

Question 1.
Discuss Simple Average of Price Relative Method. (2)
OR
Give reason:
(i) Standard deviation is the best measure of dispersion.
(ii) When correlation coefficient (r) is between + 0.75 and + 1, high degree of positive correlation and when it is between – 0.75 to -1 ,high degree of negative correlation. (2)

Question 2.
Compute Coefficient of correlation from the following data:

	X-Series	Y-Series
Mean	25	38
Sum of Squares of Deviation from Mean	225	324

The Sum of products of deviation of X and Y-series from their respective mean is 30. A number of pairs of observations is 10. (2)
OR
Average daily wage of 100 workers of a factory was ₹400 with a standard deviation of ₹80. Each worker is given a raise of ₹40. What is the new average daily wages and standard deviation? Have the wages become more or less uniform? (2)

Question 3.
When does a production function satisfy increasing returns to a factor? (2)

Question 4.
A firm supplies 10 units of a good at a price of ₹5 per unit. Price elasticity of supply is 1.25. What
quantity will the firm supply at a price of ^ 7 per unit? (2)
OR
Explain any two causes of “Decrease” in supply of a commodity. (2)

Question 5.
Why can a firm not earn abnormal profits under perfect competition in the long run₹Explain. (2)

Section – B
(3 Marks Each)

Question 6.
Calculate the correlation coefficient between X and Y and comment on their relationship. (3)

X	-3	-2	-1	1	2	3
Y	9	4	1	1	4	9

Question 7.
Complete the following schedule : (3)

Units Produced	TPP(in₹)	APP (in₹)	MPP (in₹)
1	150
2			190
3		180
4	640

Read the hypothetical case study and answer the Q. 8 and Q. 9 that follows:

The slope of a total revenue curve is particularly important. It equals the change in the vertical axis (total revenue) divided by the change in the horizontal axis (quantity) between any two points. The slope measures the rate at which total revenue increases as output increases. We can think of it as the increase in total revenue associated with a 1-unit increase in output. The increase in total revenue from a 1-unit increase in quantity is marginal revenue. Thus marginal revenue (MR) equals the slope of the total revenue curve.

How much additional revenue does a radish producer gain from selling one more pound of radishes? The answer, of course, is the market price for 1 pound. Marginal revenue equals the market price. Because the market price is not affected by the output choice of a single firm, the marginal revenue the firm gains by producing one more unit is always the market price.

The marginal revenue curve shows the relationship between marginal revenue and the quantity a firm produces. For a perfectly competitive firm, the marginal revenue curve is a horizontal line at the market price. If the market price of a pound of radishes is $0.40, then the marginal revenue is $0.40. Marginal revenue curves for prices of $0.20, $0.40, and $0.60. In perfect competition, a firm’s marginal revenue curve is a horizontal line at the market price.

Price also equals average revenue, which is total revenue divided by quantity. To obtain average revenue (AR), we divide total revenue by quantity, Q. Because total revenue equals price (P) times quantity (Q), dividing by quantity leaves us with price.

Source: Price, Marginal revenue, and Average revenue-open; Textbook for Hong Kong.

Question 8.
State the relation between marginal revenue and average revenue. (3)

Question 9.
Define Marginal Revenue. Explain the relationship between Total Revenue and Marginal Revenue. (3)

Question 10.
What are the effects of ‘price-floor’ (minimum price ceiling) on the market of a good? Use diagram. (3)
OR
The following table shows the total revenue and total cost schedules of a competitive firm. Calculate the profit at each output level. Determine also the market price of the good.

Quantity Sold	TR(₹)	TC (₹)	Profit
0	0	5
1	5	7
2	10	10
3	15	12
4	20	15
5	25	23
6	30	33
7	35	40

Section – C
(5 Marks Each)

Question 11.
(a) Calculate Standard Deviation and coefficient of variation from the following data:

Marks	Below 20	Below 40	Below 60	Below 80	Below 100
Number of Students	8	20	50	70	80

OR
Write short notes on Degree of Correlation.

Question 12.
Construct Index Number of price of 2011 from the following data by:
(i) Laspeyre’s Method
(ii) Paasche’s Method
(iii) Fisher’s Method

Commodity	2001		2011
	Price	Quantity	Price	Quantity
A	10	30	12	35
B	9	10	11	15
C	8	15	10	20
D	6	20	7	25

Question 13.
Market for a good is in equilibrium. The supply of good “decreases”. Explain the chain of effects of this change. (5)

Students can access the CBSE Sample Papers for Class 11 Physics with Solutions and marking scheme Term 2 Set 3 will help students in understanding the difficulty level of the exam.

CBSE Sample Papers for Class 11 Physics Standard Term 2 Set 3 for Practice

Time Allowed: 2 Hours
Maximum Marks: 40

General Instructions:

• There are 12 questions in all. All questions are compulsory.
• This question paper has three sections: Section A, Section B and Section C.
• Section A contains three questions of two marks each, Section B contains eight questions of three marks each, Section C contains one case study-based question of five marks.
• There is no overall choice. However, an internal choice has been provided in one question of two marks and two questions of three marks. You have to attempt only one of the choices in such questions.
• You may use log tables if necessary but use of calculator is not allowed.

Section – A (2 Marks Each)

Question 1.
Identical springs of steel and copper are equally stretched. On which, more work will have to be done?

Question 2.
How does the density of liquid vary with temperature ? Show that on increasing temperature by AT, density of liquid is given by
ρ_t = ρ(1 – γΔT)
where p is the initial density of the liquid and y is its coefficient of cubical expansion.
OR
Why is it impossible for a ship to use the internal energy of sea water to operate its engine ?

Question 3.
How does an atomiser work ?

Section – B (3 Marks Each)

Question 4.
State and prove Stefan-Boltzmann law.

Question 5.
Define root mean square velocity of gas molecules. Give various relations for it.

Question 6.
A wire of length L and radius r is clamped rigidly at one end. When the other end of the wire is pulled by a force f, its length increases by l. Another wire of the same material of length 2L and radius 2r, is pulled by a force 2f. Find the increase in length of this wire.

Question 7.
The initial state of a certain gas is (f>,VirTt). It undergoes expansion till its volume becomes VyConsider the following two cases:
(a) the expansion takes place at constant temperature.
(b) the expansion takes place at constant pressure.
Plot the P-V diagram for each case. In which of the two cases, is the work done by the gas more?

Question 8.
What are beams ? Obtain the expression for its time period when supported at both ends.
OR
The frequency of oscillations of a mass m suspended by a spring is f₁. If the length of the spring is cut to one-half, the same mass oscillates with frequency f₂. Determine the value f₂/f₁.

Question 9.
Consider a pair of identical pendulums, which oscillate with equal amplitude independently such that when one pendulum is at its extreme position making an angle of 2° to the right with the vertical, the other pendulum makes an angle of 1° to the left of the vertical. What is the phase difference between the pendulums?

Question 10.
What is column pressure ? Derive a relation for the same.

Question 11.
What is transverse wave motion ? Give examples.
OR
Given below are some examples of wave motion. State in each case, if the wave motion is transverse, longitudinal or a combination both.
(i) Motion of a kink in a long coil spring produced by displacing one end of the string sideways.
(ii) Waves produced in a cylinder containing a liquid by moving its piston back and forth.
(iii) Waves produced by a motor boat sailing in water.
(iv) Light waves travelling from sun to earth.
(v) Ultrasonic waves in air produced by a vibrating quartz crystal.

Section – C (5 Marks)

Question 12.
Case Study: Longitudinal and transverse wave:
Longitudinal Waves are defined as waves those are capable of displacing the medium in a direction either in the direction of the waves or opposite. Longitudinal mechanical waves are known as compressional waves. This is because these mechanical waves produce a lot of compression and rarefaction while travelling through medium. These waves are also called as pressure waves as three is an increase and decrease in pressure while travelling.

Sound Waves like vibrations, P-Waves created through earthquakes, etc., are some kinds of longitudinal waves.

A transverse wave is defined as the wave that moves in the perpendicular direction of the vibration. One of the most important examples of transverse waves includes the waves created by the drum’s beating. The membrane of the drum moves perpendicular to the surface. Another example of a transverse wave is light. Transverse waves travels through crests and troughs.

Transverse waves are mostly present in solids those have profound elasticity. In some cases, when there is a deformation in the material, the wave is called a shear wave.
(i) Which wave is also known as shear wave?
(a) Longitudinal wave,
(b) Transverse wave
(c) Both (a) and (b)
(d) None of these [1]

(ii) Which wave is also known as compressional wave?
(a) Longitudinal wave
(b) Transverse wave
(c) Both (a) and (b)
(d) None of these

Students can access the CBSE Sample Papers for Class 11 Economics Education with Solutions and marking scheme Term 2 Set 2 will help students in understanding the difficulty level of the exam.

CBSE Sample Papers for Class 11 Economics Term 2 Set 2 with Solutions

Time : 2 Hours
Maximum Marks : 40

General Instructions:

• This is a subjective question paper containing 13 questions.
• This paper contains 5 questions of 2 marks each, 5 questions of 3 marks each and 3 questions of 5 marks each.
• Section A, 2 marks questions are Short Answer Type Questions-Answer them in 30-50 words.
• Section B, 3 marks questions are Short Answer Type Questions-Answer them in 50-80 words.
• Section C, 5 marks questions are Long Answer Type Questions-Answer them in 80-120 words.
• This question paper contains Case/Source Based Questions.

Section – A
(12 Marks Each)

Question 1.
Explain ‘homogeneous products’ as a characteristic of a perfectly competitive market. (2)
OR
Explain the implication of “Perfect Knowledge about Market” under perfect competition. (2)
Answer:
In a perfectly competitive market, buyers treat the product produced by different firms as homogeneous. So they are willing to pay the same price for products of different firms. No firm, therefore, can charge a price higher than the market-determined price.
OR
‘Perfect Knowledge about Market’ means both buyers and sellers are fully informed about the market prices. Therefore, no firm is in a position to charge a different price and no buyer will pay a higher price. As a result, a uniform price prevails in the market.

Question 2.
Construct the index number by Simple Average of Price Relative Method. (2)

Answer:
Construction of Index Number:

\(\begin{aligned}
\mathrm{P}_{01} &=\frac{\Sigma\left(\begin{array}{l}
\mathrm{P}_{1} \\
\mathrm{P}_{0} \times 100
\end{array}\right)}{\mathrm{N}} \\
&=\frac{649.3}{6}=108.2
\end{aligned}\)

Commonly Made Error

• Students often find it difficult to understand the term simple average of price relative method.

Answering Tip

• Recall the formula of Simple Average of Price Relative Method

Question 3.
Discuss in brief, any one consequence of imposition of floor price. (2)
Answer:
(i) Surpluses: The quantity actually brought and supplied will shrink as a direct consequence of price flooring, as a result, a part of producer’s stock will remain unsold.

(ii) Buffer Stock: In order to maintain the support price, the government may design some programmes to enable producers to dispose of their surplus stocks. One such programme can take the form of buffer stock. Government may purchase the surplus to store or sell it at subsidised prices. Subsidy is required to lower the price and make it competitive in the market. Government may also use it as aid and send it to other countries. (any one to be explained)

Question 4.
List any five characteristics of an ideal measure of dispersion. (2)
OR
Which measure of dispersion is the best and how?
Answer:
An ideal measure of dispersion should possess the following characteristics:

• It should be simple to understand.
• It should be easy to calculate.
• It should be based on all the observations of the series.
• It should be rigidly defined.
• It should be suited for further algebraic treatment. (mention any 2)

OR
Standard deviation is considered to be the best measure of dispersion and is therefore, the most widely used measure of dispersion.

• It is based on all values and thus, provides information about the complete series. Because of this reason, a change in even one value affects the value of standard deviation.
• It is independent of origin but not of scale.

Question 5.
Write short notes on the following: (2)
(i) Negative Correlation.
(ii) Positive Correlation.
OR
What is scatter Diagram ? What are its demerits?
Answer:
(i) Negative Correlation: Correlation is said to be negative or inverse, if the variables move in the opposite directions. For example, when the supply of a commodity increases, the price of commodity comes down.

(ii) Positive Correlation: When both the variables are moving in the same direction, correlation is said to be positive. For example, increase in the demand of a commodity tends to increase the price of commodities.

OR

It is a technique to usually examine the relationship between variables in a visual manner. It is obtained by plotting the values of the variables on X-axis and Y-axis on graph paper.

Demerits:

• It does not exactly determine the correlation coefficient.
• It cannot be interpreted by persons who do not understand the basic term like downward sloping and upward sloping, etc.

Section – B
(3 Marks Each)

Question 6.
What does a consumer price index for industrial workers measure? (3)
OR
Given the following data:

Source: Economic Survey, Government of India, 2004-2005
Comment on the relative values of the Index numbers. Are they comparable?
Answer:
A Consumer Price Index for Industrial Workers measures the impact of changes in the retail prices on the cost of living of industrial workers. In a country like India, CPI for industrial workers is estimated and published by the Labour Bureau, Shimla taking 1982 as the base year for the current series.

In India, CPI for industrial workers is the most popular index and is used by the government to regulate Dearness Allowance (D.A.) to compensate its employees against the price rise. The weight schemes in CPI for Industrial Workers include food, pan, supari, tobacco, fuel and lighting, housing, clothing, and miscellaneous expenses.

Food being the most important component has the highest weight. Thus, it implies that the food price changes have a significant impact on the CPI.

OR
(i)

• The values of CPI of industrial workers with base year 1982 are largest and the values of WPI are least for the whole period from 1993-96 to 2003-04.
• There were many ups and downs in the CPI of non-manual employees.
• There were many ups and downs in the CPI of agricultural labourers.

(ii) The index numbers are not comparable because of the following reasons:

• Base periods are different.
• Commodities for different index numbers may be different.
• The weightage given to different index numbers of different commodities may vary from one index number to another.

Question 7.
Calculate Karl Pearson’s coefficient of correlation from the following data:

Read the passage below and answer Q8. and Q9. that follows:

Monopsony refers to a market situation when there is a single buyer of a commodity or service. It applies to any situation in which there is a ‘monopoly’ element in buying.

For example, when consumers of a certain commodity are organised, or when a socialist government regulates imports, or when a certain individual happens to have a taste for some commodity which no one else requires, or when a single big factory in an isolated locality is the sole buyer of some grades of labour, there is monopsony.

Monopsony can be formally defined, in the words of Liebhafsky, as “the case of a single buyer who is not in competition with any other buyers for the output which he seeks.to purchase, and as a situation in which entry into the market by other buyers is impossible”.

The analysis of monopsony pricing is similar to that under monopoly pricing. Just as a monopolist is able to influence the price of the product by the amount he offers for sale, similarly the monopsonist is able to influence the supply price of his purchases by the amount he buys.
Answer:


Commonly Made Error

• Students usually give wrong, explanation when it comes to define assumed mean method.

Answering Tip

• Use assumed mean Method for calculation.

Question 8.
How is monopsony different from monopoly? (3)
Answer:
Ideal market conditions are not existent everywhere and there are situations where the market is skewed either towards buyers or towards sellers. Monopoly is referred to a market condition where there is only one producer in a particular industry and the consumers really have no option but to buy his products or service.

This is an ideal condition for the player as he can dictate the terms and set the prices on his whim. The opposite condition is Monopsony where there are many sellers but a single buyer which is also an imperfect market condition.

Question 9.
Explain the concept of price discrimination under monopoly form of market. (3)
Answer:
Price discrimination happens when a firm charges a different price from different groups of consumers for an identical good or service, for reasons not associated with costs of supply.

Price discrimination takes us away from the standard assumption in that there is a single profit-maximising price for the same good or services.

For e.g. – The senior citizen discount on the train berths. Student discount in the Science Museum.

Question 10.
Explain the relationship between Marginal Cost and Average Variable Cost. (3)
Answer:

• When MC is less than AVC, AVC falls with an increase in Y output.
• When MC is equal to AVC i.e., when MC and AVC curves intersect each other at point A, AVC is constant at its u minimum point.
• When MC is more than AVC, AVC rises with an increase in output.
• Thereafter, both AVC and MC rise, but MC increases at a faster rate as compared to AVC. As a result, MC curve is steeper as compared to AVC curve.
  

Section – C
(5 Marks Each)

Question 11.
Explain the distinction between “decrease in supply” and “contraction in supply”. Use diagram. (5)
Answer:

“Contraction in Supply” means fall in quantity supplied due to fall in price of the good only, other factors remaining unchanged. For example, fall in supply from OQ₁ to OQ₂ is on account of fall in price from OP₁ to OP₂.

Reason for contraction in supply – Decrease in price of the commodity Other name – Downward movement along the supply curve. “Decrease in Supply” means fall in supply due to factor other than the price of the good. For example, fall in supply from OQ₁ to OQ₂ is at the same price. It means that some other factor has caused this price change.

Reason for decrease in supply :
Industrial Dispute: They lead to loss in the production of goods, leading to fall in supply and rise in prices.

Shortage of factors of production: This takes place when economy functions at full employment or close to full employment level and production of goods and services decreases.

Natural calamities: Floods, droughts, etc. greatly affect the supplies of agricultural goods and products. Shortage of food products and their raw materials, lead to the reduction of industrial goods and it also raises the production cost.

Hoarding of goods: Some traders hoard essential goods in order to earn more profit. It leads to artificial scarcity of goods in the market and also puts a lot of inflationary pressure.

Question 12.
(a) Calculate Average Variable Cost at each level of output: (2)

Output (Units)	MC (₹)
1	13
2	9
3	8
4	10
5	15
6	17

(b) What is average fixed cost of a firm ? Why is an average fixed cost curve a Rectangular Hyperbola? Explain with the help of a diagram. (3)
Answer:
(a)

Change in TVC is MC. Thus, by adding MC we get the TVC.

Commonly Made Error

• Students usually get confused relation between MC and TVC or relation between MC and AVC.

Answering Tip

• Recall the relation between MC and TVC and use the formula for the calculation.

(b) Per unit fixed cost is known as Average Fixed Cost. As the value of Total Fixed Cost doesn’t very at any level of output in short-run and if it is divided by an incremental number the result would be diminishing with the same proportion as that of the proportion of increases of the number of units and the product will be same.

Since TFC remains same at different levels of output, AFC falls as the level of output is increased. The AFC keeps on falling as the level of output increases. AFC can never become zero.

Question 13.
Find the Standard Deviation by Assumed Mean Method. (5)

OR
(a) Find the mean deviation about median from the following data:

(b) List the merits of Standard Deviation. (2)
Answer:

Students can access the CBSE Sample Papers for Class 11 Physics with Solutions and marking scheme Term 2 Set 2 will help students in understanding the difficulty level of the exam.

CBSE Sample Papers for Class 11 Physics Standard Term 2 Set 2 with Solutions

Time Allowed: 2 Hours
Maximum Marks: 40

General Instructions:

• There are 12 questions in all. All questions are compulsory.
• This question paper has three sections: Section A, Section B and Section C.
• Section A contains three questions of two marks each, Section B contains eight questions of three marks each, Section C contains one case study-based question of five marks. :
• There is no overall choice. However, an internal choice has been provided in one question of two marks and two questions of three marks. You have to attempt only one of the choices in such questions.
• You may use log tables if necessary but use of calculator is not allowed.

Section – A (2 Marks Each)

Question 1.
Derive the equation of continuity.
Answer:
Equation of continuity. Consider a non-viscous liquid in stream line flow through a tube AB of varying cross-section.
Let a₁ a₂ = area of cross-sections of the tube at A and B respectively,

υ₁ υ₂ = velocities of flow of liquid at A and B respectively.
ρ₁, ρ₂ = densities of liquid at A and B respectively.
∴ Volume of liquid entering per second at A = a₁υ₁
Mass of liquid entering per second at A = a₁υ₁ρ₁
Similarly, mass of liquid leaving per second at B = a₂υ₂ρ₂
If there is no loss of liquid in the tube and the flow is steady, then
Mass of liquid entering per second at A = Mass of liquid leaving per second at B
or a₁υ₁ρ₁ = a₁υ₁ρ₁ ………………… (1)
If the liquid is incompressible,
then ρ₁ = ρ₂
From (1) = a₁υ₁ = a₂υ₂
or aυ = (constant) ……………. (2)
This is known as equation of continuity.

Question 2.
Why the does the temperature of a gas decrease, when it is allowed to expand adiabatically ?
OR
State second law of thermodynamics.
Answer:
For an adiabatic change, the first law of thermodynamics may be expressed as
dU + PdV = 0
or PdV = – dU ………………. (i)
During expansion, dV is + υe. Therefore the equation (i) will hold, if dU is – υe, i.e., tempera-ture decreases.
OR
Kelvin’s statement: No process is possible whose sole result is the absorption of heat from a reservoir and complete conversion of the heat into work .

Clausius statement : It is not possible to transfer heat from a body at lower temperature to another at higher temperature without the help of some external energy.

Question 3.
What is beam ? What is its use ? Give an expression for the depression of a beam.
Answer:
Beam is ordinarily a bar supported at its ends.
It is used in the construction of a roof or a bridge.
δ = \(\frac{W l^{3}}{4 Y b d^{3}}\)
Here, all alphabets are in their usual meanings.

Section – B (3 Marks Each)

Question 4.
If the coefficient performance of a refrigerator is 5 and operates at the room temperature (27°C), find the temperature inside the refrigerator.
Answer:
Given: β = 5, T₁ = 27°C = 27° + 273 = 300 K
Coefficient performance of refrigerator,
β = \(\frac{T_{2}}{T_{1}-T_{2}}\)
5 = \(\frac{T_{2}}{300-T_{2}}\) ⇒ T₂ = 1500 – 5T₂
T₂ 5T₂ = 1500
6T₂ = 1500
T₂ = \(\frac{1500}{6}\) = 250K
T₂ = 250 – 273
T₂ = -23° C

Question 5.
For Brownian motion of particles of suspensions in liquid. Answer the following :
(a) What should be the typical size of suspended particles ?
(b) Bombardments of the suspended particles by molecules of the liquid are random. We should then expect equal no. of molecules hitting a suspended particle from all directions. Why is the net impact not zero ?
(c) Can the assembly of suspended particles be considered a ‘gas’ of ‘heavy molecules’ ? If so, what will be the temperature of this gas if temperature of the liquid is T ?
Answer:
(a)10^-6m.
(b) The average number of molecules hit in different directions so their net impact is not zero.
(c) Yes, since the heavy gas is in thermal equilibrium with the liquid, its temperature is equal to the temperature of liquid, i.e., T.

Question 6.
A truck is pulling a car out of a ditch by means of a steel cable that is 9.1 m long and has a radius of 5 mm. When the car just begins to move, the tension in the cable is 800 N. How much has the cable stretched? (Young’s modulus for steel is 2 × 10¹¹ Nm^-2.)
Answer:
Given:
Steel cable’s length, l = 9.1 m
Radius, r = 5 mm = 5 × 10^-3 m.
Tension in cable, F = 800 N
Young’s modulus = 2 × 10¹¹ N/m²
Youngf s modulus,
Y = \(\frac{F}{A} \times \frac{l}{\Delta l}\)‘
or
Δl = \(\frac{F}{\pi r^{2}} \times \frac{l}{Y}\)
= \(\frac{800 \times 9.1}{3.14 \times\left(5 \times 10^{-3}\right)^{2} \times 2 \times 10^{11}}\)
= 4.64 × 10^-4 m

Question 7.
Discuss strings stretched between fixed points.
Answer:
Let a spring be stretched between two points as shown in figure. Vibrations will set up in this string when it is disturbed, say from middle. The figure given below shows that vibration set up in this string appears to be similar to a half wave having wavelength \(\frac{\lambda}{2}\).

Length of the spring l = \(\frac{\lambda}{2}\)
or λ = 2l …………… (i)
If T is tension in the string and m is mass per unit length of the string, then velocity of disturbance is given by
υ = \(\sqrt{\frac{\mathrm{T}}{m}}\) ……………. (ii)
also υ = \(\frac{\text { Wavelength }}{\text { Time }}\)
= Wavelength x Frequency
= λf
or υ = 2l x f using equ (i)
or f = \(\frac{v}{2 l}\) ……………. (iii)
From equation (ii) and (iii)
f = \(\frac{1}{2 l} \sqrt{\frac{\mathrm{T}}{\mathrm{M}}}\) (∵ υ = \(\sqrt{\frac{\mathrm{T}}{\mathrm{M}}}\))

Question 8.
State Pascal’s law of transmission of fluid pressure. Explain how is Pascal’s law applied in a hydraulic lift, (with suitable diagram).
OR
A razor blade can be made to float on water. What forces act on this blade ?
Answer:
Pascal law : If gravity effect is neglected the pressure at every point of liquid in equilibrium at rest is same.

Hydraulic lift: It is used to lift the heavy loads. Its working is based on Pascal’s law. A simple hydraulic lift is shown in Figure. Here C and D are two cylinders of different areas of cross section. They are connected to each other with a pipe E. Each cylinder is provided with airtight frictionless piston. Let a, and A be the areas of cross-sections of the pistons in C and D respectively, where a < < A. The cylinders are filled with an incompressible liquid.

Let a downward force/be applied on the piston of C. Then the pressure exerted on the liquid, P = f/a.

Solutions
According to Pascal’s law, this pressure is transmitted equally to piston of cylinder D.
∴ Upward force acting on the piston of cylinder D will be
F = PA = \(\frac{f}{a}\) A = f\(\frac{\mathrm{A}}{a}\).
OR
When a razor blade is made to float on water, three forces act on the blade:

• Weight of the blade acting vertically downwards.
• Reaction on blade exerted by the liquid surface acting vertically upwards.
• Force of the surface tension on circumference of the blade acting tangentially to the liquid surface.

Question 9.
A standing wave is represented by y = 2Asin kx cos ωt. ff one of the component waves is y₁ = Asin (ωt – kx). What is the equation of the second component wave ?
Answer:
∴ y = 2Asin kx cos ωt
As 2sin Acos B = sin(A + B) + sin(A – B)
= Asin (kx + ωt) + Asin (kx – ωt)
According to superposition principle,
y = y₁ + y₂
and y₁ = Asin (ωt – kx)
= – Asin (kx – ωt)
y₂ = y – y₁ = 2Asin kx cos ωt + Asin (kx – ωt)
– Asin (kx + ωt) + 2Asin (kx – ωt)
= Asin (kx + ωt) – 2Asin (ωt – kx)

Question 10.
A particle moves with S.H.M. in a straight line. In the first second after starting from rest, it travels a distance x₁ cm and in the next second it travels a distance x₂ cm in the same direction. Prove that the
amplitude of oscillation is \(\frac{2 x_{1}^{2}}{\left(3 x_{1}-x_{2}\right)}\)
Answer:
As the particle starts from rest, it must start from the extreme position. Hence, when t = 0, x = r, where r is the required amplitude. 1
Using the relation, x = rcos ωt
or r – x₁ = rcos (ω × 1)
= rcos ω ………………. (i)
and r- (x₁ + x₂) = rcos (ω × 2)
= rcos 2ω
or r – x₁ – x₂ = r(2 cos² ω – 1) …….. (ii)
Solving (i) and (ii),
r = \(\frac{2 x_{1}^{2}}{3 x_{1}-x_{2}}\)

Question 11.
What is standing wave ? Give its characteristics.
OR
Obtain an equation of a progressive wave.
Answer:
Standing or stationary wave results when two progressive waves of same wavelength and amplitude travelling with same speed in opposite directions superimpose.
Characteristics:

1. Energy is not transferred from particle to particle.
2. Amplitude of vibration of particles is maximum at antinode and minimum (say zero) at nodes.
3. Time period of all particles is same except at nodes.
4. Wavelength and frequency of standing wave is same as that of the component wave.
5. Pressure variation is minimum at antinode and maximum at nodes.

OR
For a simple harmonic motion, displacement
y = r sin (ωt + Φ)
where r is amplitude, ω is angular velocity and Φ is phase difference
But ω = \(\frac{2 \pi}{\mathrm{T}}\) = 2πf
and Φ = \(\frac{2 \pi}{\mathrm{T}}\) x
where λ is wavelength and x is path difference.
∴ y = rsin 2π(\(\frac{t}{\mathrm{~T}}+\frac{x}{\lambda}\))

Section – C (5 Marks)

Question 12.
Case Study: Triple Point:
The temperature of a substance remains constant during its change of state (phase change). A graph between the temperature T and the Pressure P of the substance is called a phase diagram or P-T diagram.
The following figure shows the phase diagram of water and CO₂. Such a phase diagram divides the P-T plane into a solid-region, the vapour-region and the liquid-region. The regions are separated by the curves such as sublimation curve (BO), fusion curve (AO) and vaporisation curve (CO).

The points on sublimation curve represent states in which solid and vapour phases coexist. The point on the sublimation curve BO represent states in which the solid and vapour phases coexist.
Points on the fusion curve AO represent states in which solid and liquid phase coexist.

Points on the vaporisation curve CO represent states in which the liquid and vapour phases coexist.
The temperature and pressure at which the fusion curve, the vaporisation curve and the sublimation curve meet and all the three phases of a substance coexist is called the triple point of the substance.

(i) Sublimation curve represents the coexistence of
(a) Solid and liquid state
(b) Solid and vapour state
(c) Liquid and vapour state
(d) Liquid, solid and vapour state [1]

(ii) The temperature and pressure at which all the three phases of a substance coexist is called
(a) Boiling point
(b) Freezing point
(c) Triple point
(d) Melting point [1]

(iii) During phase change of a substance
(a) The temperature remains constant
(b) The temperature changes very slowly
(c) The temperature changes very fast
(d) Both temperature and pressure change very slowly [1]

(iv) The triple point of water is:
(a) 0.01 °C at 0.006 atmosphere
(b) 0.01K at 0.006 atmosphere
(c) – 0.01K at 0.006 atmosphere
(d) – 0.01°C at 0.006 atmosphere [1]

(v) Triple point of CO₂ is
(a) – 78.5° C at pressure of 1 atm.
(b) -56.4° C at pressure of 5.11 atm.
(c) -56.4 K at pressure of 5.11 atm.
(d) – 78.5 K at pressure of 1 atm. [1]
Answer:
(i) Option (b) in correct.
Explanation: The points on sublimation curve represent states in which solid and vapour phases coexist. The point on the sublimation curve BO represent states in which the solid and vapour phases coexist.

(ii) Option (c) in correct.
Explanation: The temperature and pressure at which the fusion curve, the vaporisation curve and the sublimation curve meet and all the three phases of a substance coexist is called the triple point of the substance.

(iii) Option (a) in correct.
Explanation: The temperature of a substance remains constant during its change of state (phase change).

(iv) Option (a) in correct
Explanation: From graph, the triple pint of water is 0.01° C at 0.006 atmosphere pressure.

(v) Option (b) in correct.
Explanation: From graph, the triple pint of CO₂ is -56.4° C and a pressure of 5.11 atm.