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INJSO – 2013 SOLUTIONS

1. Which of the following ecosystems will exhibit maximum fixation of carbon averaged over a year through

photosynthesis ? (A) Farm ecosystem (B) Ocean ecosystem (C) Rainforest ecosystem (D) Pond ecosystem Ans. (B) Sol. Maximum carbon fixation in a year through photosynthesis is done by oceanic ecosystem (mainly algae) 2. The human blood pigment Haemoglobin has maximum affinity towards : (A) NH3 (B) CO (C) CO2 (D) O2

Ans. (B) Sol. Maximum affinity of haemoglobin is towards CO, which is 200 times higher than O2. 3. Which of the following is a common character shown by both bryophytes and pteridophytes ? (A) Semi-parasitic gametophytic stage. (B) Presence of vascular tissues. (C) Independent gametophytic and sporophytic generations. (D) Water is essential for fertilization. Ans. (D) Sol. One thing common in both bryophytes and pteridophytes is that both needs water for fertilization. 4. Consider the following ecological pyramids I. Pyramid of numbers. II. Pyramid of biomass. III. Pyramid of energy. The one(s) which is/are always upright are : (A) I only (B) II and III only (C) III only (D) I and II only Ans. (C) Sol. Pyramid of energy is always upright as according to 10% low (rule of ecological tenth), only 10% energy is

transferred to next trophic level. 5. Respiratory quotient (R.Q.) is defined as the ratio of volume of CO2 evolved to the volume of O2 taken in

during the respiration process. Value of R.Q. depends on the nature of respiratory substrate and to the extent to which this substance is broken down into simpler product. Which of the following situation will give us the R.Q. value of infinity ?

(A) Fats used as substrate under aerobic conditions. (B) Organic acid is used as a substrate under aerobic conditions. (C) Any type of substrate used under anaerobic conditions. (D) Any type of substrate used under aerobic conditions. Ans. (C) Sol. As in anaerobic respiration no oxygen is utilized, so R.Q. anaerobic respiration is infinity.

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6. The following graph depict the rate and extent of a person’s breathing just before exercise.

Here V is the volume of air in lungs in dm3 and t is the time in seconds. Which of the following graph best

depicts the rate and extent of breathing of the same person immediately after a period of exercise ?

(A)

(B)

(C)

(D)

Ans. (C) Sol. After heavy exercise O2 availability get decreased, in order to balance this decrease in volume of oxygen,

respiration rate increases with deep breaths. 7. The following picture depicts the internal arrangement (anatomy) of bone structures in the limbs of different

organisms. Which of the following statement is the most valid inference that can be drawn from a careful analysis of the limbs of different organisms in the diagram below ?

(A) Bones of limbs of all the organisms have similar basic plan therefore may have common ancestor. (B) Bones of limbs of all the organisms have the same basic structure but different shapes, therefore bone

expression is controlled only by the environmental factor. (C) Bones of limbs of all the organisms do not have similar bone structure therefore they may have

evolved differently.

(D) Systematic increase in the number of digits (fingers) exemplify use and disuse of organs. Ans. (A) Sol. Common type of bones are present in limbs of all the organism which show that they might have got

evolved from common ancestor, decedents of which reached different environmental condition and got adapted to that environment. So their function became different (suited to that environment).

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8. Consider a beaker with a partition made up of sieved glass plate such that the beaker now contains two spaces – ‘A’ and ‘B’. The beaker contains distilled water to which sugar was added in space A.

As you see in the image, some molecules of sugar have moved to the region B. Which of the following is

the correct term for describing this process ? (A) Osmosis (B) Diffusion (C) Plasmolysis (D) Imbibition Ans. (B) Sol. In diffusion solute and solvent particles move from their higher concentration. to their lower concentration. 9. Hydrilla spp., an aquatic plant is immersed in water in a beaker. A funnel is kept inverted on it. A test tube

filled with water is inverted on the nozzle of the funnel. Four such sets are prepared and each of them is exposed to different wavelengths of light, which were as follows :

Set I : Yellow light Set II : Blue light Set III : Red light Set IV : Green light

The experiment is continued for 5 hours and the amount of oxygen evolved by the plant (measured in

terms of number of bubbles) in each set is measured. The following graph is obtained from the data which details different quantities of oxygen evolved when exposed to different quality of light A, B, C and D.

Which of the following combinations match correctly with the data represented in the graph ? (A) A – Red, B – Green, C – Blue and D – Yellow. (B) A – Green, B – Yellow, C – Red and D –Blue. (C) A – Blue, B – Red, C – Yellow and D – Green. (D) A - Yellow, B –Red, C – Blue and D – Green. Ans. (D) Sol. Maximum photosynthesis occurs in red light and minimum in green light and blue and yellow shows

intermediate condition.

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10. Monozygotic twins have : (A) Same genetic make up and different biological sex. (B) Same genetic make up and same biological sex. (C) Dissimilar genetic make up and different biological sex. (D) Dissimilar genetic make up but same biological sex. Ans. (B) Sol. As monozygotic twins are formed from same zygote, so their sex and genetic makeup will be same. 11. The life cycle of plants shows two distinct phases : a diploid (sporophytic) phase and haploid

(gametophytic) phase which alternate with each other. The generalized pattern can be represented as in the following diagram:

Afreen studies the life cycles of 3 different plants : I, II, III and made the following observations. Plant I : Shows dominant gametophyte, sporophyte semi-parasitic on parent gametophyte. Plant II : Shows reduced gametophyte, dominant sporophyte, Both phases are independent. Plant III : Shows reduced gametophyte, dominant sporophyte. Gametophyte is produced within the

sporophyte and not as separate generation. Based on the information provided, which of the following options do you think represents the correct

sequence of plant group to which plant I, II and III belong to ? (A) I : Gymnosperm, II : Pteridophyte, III : Bryophyte. (B) I : Bryophyte, II : Pteridophyte, III : Gymnosperm. (C) I : Bryophyte, II : Gymnosperm, III : Pteridophyte. (D) I : Pteridophyte, II : Bryophyte, III : Gymnosperm Ans. (B) Sol. In bryophyte: Gametophyte generation is dominant and saprophyte generation is dependent on

gametophyte. Whereas In Pteridophyte : Saprophyte generation is dominant but both the phases are green and hence

independent. 12. A section of a tissue was studied for the composition of various cell organelles. It was found that the cells

contained extensive Golgi apparatus. The organelle composition suggests predominance of which of the following activities within the cells ?

(A) Synthesis of ATP molecules. (B) Packaging of macromolecules. (C) Production of protein molecules. (D) Storage of large quantities of food. Ans. (B) Sol. Main function of golgi apparatus is modification and packaging of macro molecules. 13. Cartilage is a connective tissue that smoothens bone surfaces at the joints. It is also present in nose, ear,

trachea and larynx. Matrix of hyaline cartilage is predominantly composed of : (A) Proteins and sugar (B) Calcium and phosphorus (C) Calcium and fibres (D) Sugar and calcium Ans. (A) Sol. Hyaline cartilage matrix is made up of collagen protein, proteoglycans fibres and chondrin protein.

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14. Which of the following statement(s) is (are) correct statement(s) with respect to motor neurons ? I. They are multipolar. II. They are unipolar. III. They carry messages form CNS (Central Nervous System) to muscle fibres or glands. IV. They carry messages from sensory receptors of CNS. (A) I only (B) II only (C) I and III only (D) I and IV only Ans. (C) Sol. Motor neurons or efferent neurons are multipolar and carry messages from CNS to muscle fibres, or gland

i.e. effector organ. 15. The transitional epithelium lines inner surface of urinary bladder and ureter. This epithelial layer is thinner

and more stretchable as compared to the stratified epithelium. The best possible explanation for such a structural feature of transitional epithelium is that it:

(A) Prevents infection to the organs (B) Accommodates fluctuation of volume of the liquid in an organ (C) Enables re-absorption of salts from urine (D) Helps in micturition (process of urination) Ans. (B) Sol. Transitional epithelium lining the inner surface of urinary bladder and ureters helps to accommodates

fluctuation of volume of the liquid in these organs as it lacks basement membrane and provide more stretchability.

16. Anna is studying salt uptake (absorption) by the roots in a plant.. Which of the following features DOES

NOT play a role in the salt uptake in plants. (A) pH of the soil (B) Temperature (C) Light conditions (D) Soil bacteria Ans. (D) Sol. Salt uptake or absorption by roots in a plant takes place actively. It get affected by pH of the soil,

temperature and light conditions. 17. A rare plant in a botanical garden has been infected with specific fungi that feed on sugar molecules. After

careful examination, a botanist suggested the following surgical intervention to get rid of the fungi and prevent its spread to apical portions, removing the infected portion so that a ring of bark about 2 inches in height and about 1-2 cms wide is removed. This will remove the cambial cells, phloem, endodermis, cortex and epidermis of the stem. Which of the following will be a consequence of such a surgical intervention?

(A) Flow of food will be affected but flow of water upwards will be maintained (B) Flow of water upward will be lost but flow of food will be maintained (C) Both flow of food and water upward will be lost (D) Neither the flow of food nor water movement will be affected Ans. (A) Sol. On removing ring of bark about 2 inches in height and about 1-2 centimetres wide also removes cambial

cells, phloem, endodermis, cortex and epidermis of stem but not xylem that’s why flow of food will be affected but flow of water will be maintained.

18. In a bee hive, there are thousand of worker bees performing number of day-to-day activities. Genetically,

the worker bees are : (A) Sterile males (B) Fertile (C) Fertile females (D) Sterile females Ans. (D) Sol. Worker bees are sterile females 19. In certain plant species, red flower colour is incompletely dominant to white flower colour. (the hetrozygote

is pink) and tall stems are completely dominant to dwarf stems. If the pink plant (TtRr) is crossed with a tall white plant(TTrr), which of the following types of plants would be produced in the offsprings?

(A) Dwarf pink and tall red (B) Tall pink and tall white (C) Dwarf red and tall pink (D) Tall pink and dwarf white Ans. (B) Sol. Cross between (Tt Rr) and (TT rr) results in production of tall pink and tall white plants.

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20. Consider the following characters I. Flowers with trimerous symmetry II. Vascular bundles scattered in ground tissue. III. Leaves with reticulate venation Iv. Plant with tap root system The characters exhibited by monocotyledons are : (A) I and III only (B) ) III and IV only (C) ) I and II only (D) ) II and IV only Ans. (C) Sol. Monocots have trimerous flower, scattered vascular bundles, parallel venation and fibrous roots. 21. Which of the following secretions of the alimentary canal in human DO NOT contain any enzymes? (A) Salivary Juice (B) Gastric juice (C) Bile Juice (D) Pancreatic juice Ans. (C) Sol. Bile juice secreted by liver cells does not contain any enzymes. 22. Humans are called ureotelic animals as they excrete nitrogen primarly in the form of urea. However, urine

of a healthy human being also contains traces of uric acid. The source of this waste product is (A) Metabolism of DNA and RNA (B) Lipid metabolism (C) Carbohydrate metabolism (D) Protein metabolism Ans. (A) Sol. Nucleic acid metabolism results in formation of uric acid. Answer question number (23-25) based on the following passage A farmer is growing a crop regularly in his field. He uses chemical fertilizers, pesticides, organic manure as

well as bio-fertilizers. Very close to his field is a factory which emits smoke as a by product. There is also a huge lake in the near by area.

23. A considerable increase in plant life in the lake was noticed after the farming activity intensified. The most

likely reason for this could be (A) Chemical fertilizers leached into the lake from the field (B) Pesticides leached into the lake from the field

(C) Organic manure leached into the lake from the field. (D) Smoke particles from the industry got settled in moist surrounding of the lake. Ans. (A) Sol. Chemical fertilizers leached into the lake from the field cause enormous growth of plants by increasing

availability of nutrients (Nitrogen, phosphate) for plant growth. 24. Consider the following food chain in the same lake

Aquatic plant Small fish Big fish Birds Which of the above organism is likely to show minimum amount

(A) Aquatic plants (B) Small fish (C) Big fish (D) Birds Ans. (A) Sol. In bio magnification amount of pesticide increases by increasing trophic level. Because aquatic plants lie at

first trophic level so they will have minimum amount of pesticide. 25. An expert agriculturist, suggest to the farmer to minimize the use of chemical fertilizers and instead use

biofertilizers as they have many advantages over chemical fertilizers. Which of the following is not true for biofertilizers

(A) There are economical (B) They help in reducing pollution in the lake (C) They are renewable (D) They require large set-up for their production Ans. (D) Sol. Bio-fertilizers do not require large set up for their production they can be easily grown in normal conditions.

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26. The density of water at room temperature is 1g/ml (mili-liture). Consider a spherical drop of water having volume 0.05 ml. The drop evaporates at a uniform rate in one hour. The number of molecule leaving the liquid surface per second is approximately

(A) Zero (B) 5 × 1017 (C) 3 × 1014 (D) 2 × 1021

Ans. (B) Sol. Volume = 0.05 ml Density = 1 gm/ml Mass = 0.05 gm

Moles = 0.0518

No. of molecules = 30.05 6.023 1018

= 1.67 × 1021 So no. of molecules evaporate per sec.

=

21171.67 10 4.6 10

3600per sec.

27. 50 ml of 0.20 M solution of washing soda reacts with one of the acids in aqua regia. One of the procucts is

Chile saltpetre. If the strength of the acid is 0.25 M, What volume of it will be required to react with the above solution.

(A) 40 ml (B) 10 ml (C) 20 ml (D) 80 ml Ans. (A) Sol. Na2CO3 . 10H2O + HNO3 NaNO3 + CO2 + H2O (chile salt petre) N1V1 = N2V2 2× 0.20 × 50 = 0.25x

x = 2 0.20 50 80ml0.25

28. Oxides are acidic, basic or amphoteric based on their metallic or non-metallic character. Which one of the

following oxides reacts with both HCl and NaOH. (A) CaO (B) ZnO (C) SO2 (D) CO2 Ans. (B) Sol. ZnO is an amphoteric oxide. 29. 1.84 g of Dolomite (CaMg(CO3)2) ore was heated resulting in a residue of constant weight 0.96 g. During

heating the metal of one of the products burnt with a brick red flame and the second burnt with a dazzling white flame. The approximate percentage composition of the two products in the residue are respectively:

(A) 54 and 46 (B) 46 and 54 (C) 42 and 58 (D) 58 and 42 Ans. (D) Sol. CaMg(CO3)2 CaO + MgO + 2CO2 1.84 gm 0.96 gm

Moles of dolomite = 1.84 0.01184

Moles of CaO = 0.01 = Moles of MgO Wt. of CaO = 0.01 × 56 = 56 gm = 58% Wt. of MgO = 40 gm = 42%

30. Colloid consists of dispersed phase and dispersion medium. Aerosol is one type of colloid. Aerosol is made

up of which of the following combination ? I. Gas in liquid II. Liquid in gas III. Solid in gas (A) II only (B) I, II and III (C) I and II only (D) II and III only Ans. (D) Sol. Aerosol Gas as dispersion medium.

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31. Tyndall effect can be observed in a colloidal solution. Consider light scattering in the following : I. When sunlight passes through the canopy of a dense forest. II. When normal light passes through lead iodide solution. III. When monochromatic light passes through solution of K2SO4(Al)2SO4.24H2O. Tyndall effect is observed in: (A) I, II and III (B) I only (C) I and III only (D) III only Ans. (B) Sol. Only I is an example of colloidal solution. 32. A compound used for cleaning purpose having hydrophobic and hydrophilic ends is : (A) Sodium or potassium salt of saturated or unsaturated fatty acids. (B) Triglycerides of saturated or unsaturated fatty acids (C) Monoesters of saturated or unsaturated fatty acids (D) Triglycerides of unsaturated fatty acids Ans. (A) Sol. Sodium and potassium salt of saturated or unsaturated fatty acids having hydrophobic & hydrophilic end

and used for cleaning purpose. 33. Hydrogenation is a reaction in which hydrogen is added to a compound. One of the applications of

hydrogenation reaction is to convert unsaturated compounds into saturated ones. This reaction is applicable to which of the following compounds ?

(A) Ethyl alcohol (B) Chloroethane (C) Vegetable oil (D) Animal fat Ans. (C) Sol. Vegetable oils contain unsaturated bonds and by the process of hydrogenation it is converted into

saturated compounds. 34. One of the tests used to distinguish a saturated from an unsaturated compound is bromine water test.

Ethene and ethane are reacted with bromine water and the results are displayed on the table given below. From the following table choose the correct observation.

Ethene Ethane (A)

H C C H

Br Br

H H with decolourisation

Br C C H

Br H

H H with decolourisation (B)

Br C C H

Br H

H H with no decolourisation

Br C C H

Br Br

H H with no decolourisation (C)

H C C H

Br Br

H H with decolourisation

no reaction

(D) no reaction

Br C C Br

Br Br

H H with decolourisation Ans. (C) Sol. Unsaturated compounds decolorize Br2 water but not saturated compounds. 35. Atomic number decides chemical property of an element. It also decides which group the element belongs

to. Identify which of the following elements are from the same group in the periodic table. (A) 1, 3, 11, 19, 37 (B) 8, 24, 42, 74 (C) 4, 12, 20, 58 (D) 5, 13, 27, 47 Ans. (A) Sol. Atomic no 1, 3, 11, 19, 37 are elements of 1st group (alkali metals)

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36. Riya took two containers in which chlorine and oxygen are kept under STP with both containing the same number of molecules represented by n. The molecules of oxygen gas occupy V litres and have a mass of 8 grams. Under the same conditions, the mass and volume of 3n molecules of chlorine gas are respectively:

(A) 17.75 grams and 5.6 litres (B) 35.5 grams and 11.2 litres (C) 52.75 grams and 33.6 litres (D) 26.25 grams and 8.4 litres Ans. (C) Sol. For n molecules

moles of O2 = moles of Cl2 = 8 132 4

for 3n molecules

wt. of Cl2 = 1 3 714 = 53.25 gm

Remarks : If number of molecules are increased to 3n molecules then volume will also become thrice of initial.

so 1V 3 22.4 16.8 litre4

This is not given in any of option.

37. Esha performed a simple experiment to distinguish strong from weak acid. For this she performed qualitative experiments with universal indicator, using tamarind and the acid present in gastric juice and she recorded her observations. Which of the following findings did she observe ?

Acid present in gastric juice Acid present in tamarind Strength Colour of universal indicator Strength Colour of universal indicator

(A) Weak Red Strong Red (B) Weak Yellow Weak Green (C) Strong Light red Weak Yellow (D) Strong Green Strong Blue

Ans. (C) Sol. Gastric Juice = HCl Strong acid indications (Blue to Red) tamarind = tartaric Acid Weak Acid

38. Haber’s process for the production of ammonia is an industrially important process used mainly in fertilizer industry. Due to some accident only 10% conversion took place. If all the volumes are measured in litres at STP, what volume of reactants are needed for this conversion ?

(A) 1/2 of the total volume of hydrogen and nitrogen (B) 1/5th of the total volume of hydrogen and nitrogen (C) 1/10th of the total volume of hydrogen and nitrogen (D) 1/5th of the total volume of nitrogen Ans. (C)

Sol. 2 2 3N 3H 2NH If 10% conversion took place then 10% of total volume of reactants required. 39. Sugarcane plants are one of the most efficient converters of one form of energy to another form. What type

of energy conversion takes place in sugarcane plant ? (A) Biochemical energy to mechanical energy (B) Solar energy to chemical energy (C) Chemical energy to solar energy (D) Solar energy to magnetic energy Ans. (B) Sol. Solar energy to chemical energy takes place in sugarcane plant.

40. A solid compound X was treated with a liquid Y. During the reaction a colourless gas was evolved. The evolved gas turned lime water milky. The evolved gas when treated with acidified potassium dichromate solution turned the solution green. The aqueous solution of X gives a white precipitate when treated with barium chloride solution which is soluble in dilute HCl. Identify the anion present in compound X.

(A) carbonate (B) sulphate (C) sulphite (D) chloride Ans. (C) Sol. SO3

2– + H+ SO2 + H2O (SO2 gas turns lime water milky) K2Cr2O7 + SO2 + H+ Cr+3 + SO4

2– + H2O (Green solution) SO3

2– + BaCl2 BaSO3 + Cl– BaSO3 + HCl BaCl2 + H2SO3 (Soluble solution)

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41. X is a member of alkene series with a molecular mass 28 amu. 200 cm3 X is burnt in just sufficient air (containing 20% oxygen) to form carbon dioxide and steam. If all the measurements are made at constant pressure and 100°C, find the composition of the products formed and the unreacted air.

(A) 400 cm3, 400 cm3, 600 cm3 respectively (B) 200 cm3, 200 cm3, 2400 cm3 respectively (C) 200 cm3, 400 cm3, 2400 cm3 respectively (D) 400 cm3, 400 cm3, 2400 cm3 respectively Ans. (D) Sol. C2H4 + 3O2 2CO2 + 2H2O Volume of ethene = 200 cm3 Volume of O2 required = 600 cm3

The amount of air = 3600 100 3000cm

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Volume of CO2 & H2O = 400 cm3 Remaining volume of air = 3000 – 600 = 2400 cm3 42. Thermit reaction is one of the important reactions in the metallurgical industry. This reaction is best

described as: (A) Iron is displacing aluminium from its ore where iron acts as reducing agent and aluminium as oxidizing

agent (B) aluminium is displacing iron from its ore where iron acts as oxidizing agent and aluminium as reducing

agent (C) aluminium is displacing iron from its ore where iron acts as reducing agent and aluminium as oxidizing

agent (D) iron is displacing aluminium from its ore where iron acts as a oxidizing agent and aluminium as

reducing agent. Ans. (B) Sol.

Fe2O3 Oxidizing agent.

43. Metals are arranged in reactivity series according to their order of reactivity. Depending upon order of

metal in the reactivity series it will be extracted from its ore. Which of the following methods will be used to extract copper from its alloy cupferronickel ?

I. Electrolysis II. Reduction with Carbon III. Calcination (A) I and II only (B) I, II and III (C) II and III only (D) I and III only Ans. (A) Sol. For the extraction of Cu from alloy electrolysis and reduction with carbon required. 44. A student makes the following statement concerning Bose-Einstein Condensate (BEC) : I. It is formed at very low temperature II. It is formed at very low densities III. It was first formed by Bose and Einstein IV. It consists of ionizing super-energetic and excited particles. The correct statements regarding BEC are (A) I and II only (B) II and III only (C) I and III only (D) I and IV only Ans. (A) Sol. BEC is formed at very low temperature at very low densities. 45. Which of the following set of elements have the strongest tendency to form anions ? (A) N, O and P (B) P, S and Cl (C) N, P and Cl (D) N, P and S Ans. (A) Sol. 2nd period and due to of high lattice energy elements have the strongest tendency to form anions. 46. Halides of sodium are soluble in water. Arrange these halides in the decreasing order of their solubility. (A) NaF > NaCl > NaBr > NaI (B) NaI > NaBr > NaCl > NaF (C) NaI > NaCl > NaBr > NaF (D) NaI > NaBr > NaF > NaCI Ans. (A) Sol. Ionic character : NaF > NaCl > NaBr > NaI

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47. For a redox reaction between one mole of potassium dichromate and x moles of hydrochloric acid, products are formed out of which one product is y moles of chromyl chloride (CrCl3). The values of x and y are :

(A) 8 and 4 respectively (B) 8 and 2 respectively (C) 2 and 8 respectively (D) 4 and 8 respectively Ans. (B) Sol. K2Cr2O7 + 8HCl 2CrCl3 + 4H2O + 2KCl + 3[O] Remarks : In question chromyl chloride is given with CrCl3 formula which is wrong. Chromyl Chloride is CrO2Cl2 and CrCl3 is Chromium (III) chloride.

48. Rahul dropped 150 g of marble chips into 1 kg of HCl solution containing 0.1 of its weight of pure acid. The mass of marble chips that remained undissolved will approximately be :

(A) 6.50 g. (B) 13 g. (C) 26 g. (D) 15 g. Ans. (B) Sol. CaCO3 + 2HCl CaCl2 + CO2 + H2O

150 mole100

2 5C H OHNaOH

HCl is limiting reagent 2 mole HCl react with 1 mole

10036.5

HCl react with 1 1002 36.5

= 1.369 mole

Undissolved CaCO3 = 0.131 mole = 13.1 gram 49. Alkaline KMnO4 was added to substance A and heated. The product formed B, was isolated and reacted

with another aliquot of substance A in presence of a base to form the product C. To confirm the identity of C, a qualitative test was performed which was as follows : C was reacted with a drop of dilute NaOH solution in presence of ethanol to give product D. The observations of the above reaction were :

(A) Pink colour of the reaction mixture disappears and it has a fruity odour (B) Pink colour of the reaction mixture disappears but it does not have any characteristic odour (C) Pink colour of the reaction mixture persists and it has a fruity odour (D) Pink colour of the reaction mixture persists but it does not have any characteristic odour. Ans. (B) Sol. KMnO4 + I

– +OH

– IO3

– + Mn+4

IO3– + I– I2

I2 2 5C H OHNaOH CH3COO– + CHI3

yellow 50. Arrange the following elements in the increasing order of their atomic radii : (A) Na < Li < Rb < C < K (B) Cs < Rb < K < Na < Li (C) K < Rb < Cs < Na < Li (D) Li < Na < K < Rb < Cs Ans. (D) Sol. Down the group, atomic radii increases Li < Na < K < Rb < S 51. Estimate the order of magnitude of the pressure in N/m2 exerted on the Earth by an average adult human

being when standing bare feet on both legs : (A) 103 (B) 105 (C) 107 (D) 109 Ans. (B) Sol. Let Average weight of Human being be = 600 N Average feet area of Human being be = 150 cm2

So, P = 4–4

F 600 4 10A 150 10

pa

So, order of magnitude of the pressure is 105 in N/m2

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52. Three observers A, B and C measure the speed of light in vacuum from a source to be VA, VB and VC respectively. The observer A moves towards the source and observer C moves away from the source at the same speed. The observer B stays stationary. Consider the following expressions.

I. VA > VB > VC II. VA = VB = VC III. VB = (VA + VC) /2 IV. VB = A CV V The correct expressions are : (A) I only (B) I and II only (C) I and IV only (D) II, III and IV only Ans. (D) Sol. Speed of light measured from any reference frame is same so, VA = VB = VC

and Hence, VB = A CA C

V VV V

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53. A 2.00 kg ball and a 1.00 kg ball collide with each other. The data from their collision is shown on the table

given below :

2.00 kg ball 1.00 kg ball Time Px Py Px Py

Before collision 15.00 0.00 0.00 5.00 After Collision 12.00 9.00 3.00 –4.00

Here Px and py are x and y components respectively of linear momentum. The angle between the balls after collision is :

(A) 150° (B) 120° (C) 90° (D) 60° Ans. (C)

Sol. = –1 –19 4tan tan12 3

= 37° + 53° = 90°

y m = 2kg

m = 1 kg

xtan–1 4

3

tan–1 912

54. A monkey is holding onto one end of a light rope which passes over a frictionless pully and at the other

end there is a plane mirror which has a mass equal to the mass of the monkey. At equilibrium the monkey is able to see her image in the mirror. Consider three situations :

I. The monkey climbs up the rope. II. The monkey tries to push the rope down. III. The monkey lets go of the rope. Under which of the above conditions does the monkey continue to see her image? (A) I only (B) II only (C) III only (D) I, II and III Ans. (D) Sol. Net force acting on monkey and mirror is same so their relative acceleration is zero, hence in all the

situations monkey continue to see her image. 55. A lens is held directly above a pencil lying on a floor and forms an image of it. After the lens has been

moved vertically a distance equal to its focal length, it forms image of equal size to the previous image. If the length of the pencil is 8 cm, the length of the image is :

(A) 8 cm. (B) 12 cm. (C) 16 cm. (D) 24 cm. Ans. (C)

Sol. Magnification for len’s,m = ff u

Now, Let initial distance of lens and pencil to be x

So, ff – x

= –ff(x f )

fx2

Now, m = f 2ff –2

So, height image of pencil is 16 cm.

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56. A steel ball is dropped from a height of 1 m on to a horizontal non-conducting surface. Every time it bounces, it reaches 80% of its previous height. Nearly by how much will the temperature of the ball rise after 4 bounces? Specific heat capacity of the ball (steel) = 0.1 cal/g-°C. Neglect loss in heat to the surroundings and the floor.

(A) 0.014 °C (B) 0.059°C (C) 0.59 °C (D) 1.4 °C Ans. (A) Sol. Total mechanical energy lost by ball = Heat energy gain by ball 2 3 4m g 1 0.2 (0.2) (0.2) (0.2) m 420 T

2 3 4[0.2 (0.2) (0.2) (0.2) ]T

42

0.014°C 57. A circular metal washer is uniformly heated. Select the correct statement. (A) Both its external and internal diameters increase (B) Its external diameter increases and internal diameter decreases (C) Its external diameter is unchanged and internal diameter decreases (D) Its external diameter increases and internal diameter is unchanged Ans. (A) Sol. Distance between any two points on metal washer will increase 58. Books A and B are made from paper of the same roll. The dimensions of book B are double those of book

A. Both the books are kept with their largest area flat on a horizontal table. Select the correct statement . (A) Volume of book B is 6 times that of book A. (B) Pressure exerted by book B on the table is 4 times that by book A. (C) Weight of book B is 4 times that of book A (D) None of the statements above is correct Ans. (D) Sol. As per given data 8VA = VB

4AA = AB

8WA = WB

2PA = PB

So, None of the statements is correct. 59. A hot solid at temperature t1 is placed in a cool liquid at temperature t2. Both acquire a common

temperature t0. Then : (A) t0 = (t1 + t2) / 2 always (B) t0 > (t1 + t2)/2 if mass of solid is greater than the mass of the liquid (C) t0 > (t1 + t2) / 2 if specific heat capacity of solid is greater then the specific heat capacity of the liquid

(D) Information provided is insufficient to draw any of the above conclusion. Ans. (D)

Sol. t0 =

1 1 1 2 2 2

1 1 2 2

m s t m s tm s m s

2 21 2

1 10

2 2

1 1

m st tm s

tm s1m s

So, information provided is insufficient to draw any of the given conclusion. 60. A 100 m sprinter increases her speed from rest uniformly at the rate of 1 m/s2 upto 40 m and covers the

remaining distance with uniform speed. The sprinter covers the first half of the run in t1 s and the second half in t2s. Then :

(A) t1 > t2 (B) t1 < t2 (C) t1 = t2 (D) information given is incomplete

14

Ans. (A)

Sol. t1 = 2 40 10 901 80 80

t2 = 5080

So, t1 > t2

40 m

t1 t2

50 m 50 m

80 m/s U = 0 v =

61. Rain is falling vertically with a speed of 1.7 m/s. A girl is walking with speed of 1.0 m/s in the N – E (north -

east) direction. To shield herself she holds her umbrella making an approximate angle with the vertical in a certain direction. Then :

(A) = 60° in N – E direction (B) = 30° in N – E direction (C) = 60° in S – W direction (D) = 30° in S – W direction Ans. (B)

Sol. 1 301.7

North East

62. The atmospheric pressure on the earth’s surface is PaN/m2. A table of area 2 m2 is tilted at 45° to the

horizontal. The force on the top surface of the table due to the atmosphere is (in newtons) : (A) 2 Pa (B) a2P (C) a2 2P (D) aP / 2 Ans. (A) Sol. Thrust = Area × Pressure = 2Pa 63. The ratio of the size of the atom to the size of the nucleus is typically : (A) 10 (B) 102 (C) 104 (D) 108 Ans. (C)

Sol. Size of AtomSize of roules

= –10

5–15

10 1010

64. A mixture of 50 g of ice and 50 g of water, both at 0°C, is kept in a calorimeter of water equivalent 22 g. 30

g of steam is slowly and uniformly passed through this mixture. Neglecting exchange of heat to the surrounding (except for the steam). final temperature of the mixture and mass of the contents (water) in the calorimeter is :

(A) 100°C, 130 g (B) 0°C, 130 g (C) 100°C, 126 g (D) 66.7°C, 120 g Ans. (A) Sol. Usable heat of steam to convert in 100° water = 30 × 540 = 16200 cal. Heat required to heat water + ice + calorimeter upto 100°C = (50 × 80) + (50 + 50 + 22) × 100 = 4000 + 12200 = 16200 Cal. So final temp. = 100°C Content = 50 + 50 + 30 = 130 gm water 65. In heating experiment in which heat is supplied at a steady rate it was noted that temperature of the liquid

in a beaker rose at 4K/minute just before it began to boil and 40 minutes later all the liquid had boiled away. Numerical ratio of specific heat capacity to specific latent heat (in same system of units) for this liquid is :

(A) 1/10 (B) 1/40 (C) 1/160 (D) 1/640 Ans. (C) Sol. m × s × 4 = R m × L = 40 R

s 1L 160

15

66. The natural voices of men, women and children are different and can be distinguished. A student makes three hypotheses :

I. The amplitudes of sounds emitted by them are different II. The vocal cords are of different sizes. III. The vocal cords vibrate with different frequencies The correct option is : (A) I only (B) II only (C) III only (D) I and III only Ans. (B) Sol. The natural voices of men, women and children are different and can be distinguished as there vocal cords

are of different sizes making the quality of sound different. 67. On a hot, dry summer day a boy is standing between plane parallel vertical cliffs separated by 75m. He is

30 m away from one of the cliffs. Consider speed of sound in air on that hot day to be 360 m/s. The boy claps loudly and hears its successive echoes. The time in seconds at which he hears the first four echoes are respectively :

(A) 1 1 1 5, , ,6 4 12 12

(B) 1 1 7 2, , ,6 4 12 3

(C) 1 1 5 7, , ,4 3 12 12

(D) 1 1 1 5, , ,6 4 3 12

Ans. (A) Sol. Let time to hear successive echoes to be t1, t2, t3 & t4 then,

t1 = 22 30 1 2 45 1; t360 6 360 4

t3 = t4 = 150 5360 12

30 m 45 m

75 m

68. A load that has resistance of 10 is to be connected to be connected to a constant voltage (120 V) supply.

Desired variation in the current through the load is from 3 A to 5A. The resistance and current range of the rheostat should be :

(A) 0 -36, 0-5 A (B) 14 -24, 0-3 A (C) 14 -30, 0-5 A (D) 0 -24, 3-5 A Ans. (C) Sol.

h

120 3R 10

h

120 5R 10

h120 3R 30 120 = 5Rh + 50 90 = 3Rh 70 = 5Rh Rh = 30 Rh = 14 69. Point charges q1 = +1C and q2 whose magnitude is 64/27 C are fixed 5 m apart along a veritical line

with q1 being at lower position. These two charges together are able to hold an oil drop of mass 1g and charge Q stationary when it is 3 m away from q1 and 4 m away from q2. The sign of the charge q2 and the value of Q are respectively

(A) q2 is positive Q = 6.25 pC (B) q2 is positive Q = 6 pC (C) q2 is negative Q = 6.25 pC (D) q2 is negative Q = 6 pC Ans. (B)

16

Sol. q2 must be negative to balance the oil drop.

To balance the oil drop, Net upward force = Weight of oil drop

Net upward force = 2 21 2F F

F1 =

9 6

32

9 10 Q 10 Q 10 N3

F2 =

9 63

2

649 10 Q 10 9 64Q 102716 274

= 34 Q 10 N3

Net upward force =

3316 5Q 101 Q 10

9 3

395Q 10 10 10

3

Q = 8 33 10 105

Q = 0.6 × 10–11 Q = 6 pC Answer question numbers 70 and 71 based on the following passage

A cubic box of height h and mass m floats upright in a liquid of density in position (1) as depicted in the

figure. When a downward force of magnitude F is applied on the top of the block, the block moves down through a distance y with some part of the block being still above the liquid in position (2) as shown in the figure. Force F is now suddenly removed so that the block start moving up. Neglect the effect of viscosity throughout the motion

70. Consider the following statement I. At position (1), the vertical distance from surface of the liquid to the bottom of the block is m/h2 II. After removal of force F, the upward velocity of the block continuously increases until it reaches

position. (1) III. During upward motion, after crossing position (1), the velocity of the block goes on decreasing. IV. During upward motion, from position (2), the velocity of the block increases linearly till it reaches

position (1) Which of the above statement are correct? (A) I, II, III and IV (B) I, II and III only (C) I and III only (D) I and II only

17

Ans. (B) Sol. Statement-I : mg = x Ag

x = 2

m mA h

True

Statement-II : After removal of F, a net upward force (variable) acts on the object till it reaches from position (2) to

position (1). So velocity continuously increases. True Statement-III : After crossing position (1), net downward force starts acting on the box. So velocity decreases True Statement-IV : During upward motion, net acceleration is not constant. Velocity will not increase linearly False 71. Let W be the weight of the block. Upthrust (U) experienced by the block is plotted against upward distance

(d) travelled by the block from position (2) until it reaches position (1) . Select the option showing correct nature of the graph (A)

(B)

d

(C)

d

(D)

Answer question numbers 72 and 73 based on the following information. Solar surface radiates energy uniformly at a rate of 4 × 1026 W. This energy spreads or distributes

uniformly and normally outwards. Ans. (B) Sol. U = xAg (x = depth within liquid) U decreases linearly with distance travelled.

18

72. Considering Earth and the Sun to be spherical object, the amount of radiant energy received by the Earth per second is nearly :

(A) 1360 W (B) 1.75 × 1017 W (C) 3.5 × 1017 W (D) 7 × 1017 W Ans. (B) Sol. Energy received per second by an area 1m2 on earth’s surface.

=

26

11 21 4 10

4 (1.5 10 )

=

25

2210 10

3.14 2.25 10

=

253

2210 10 1.4 10 J

7.065 10

Solar constant = 1.4 Kw/m2 Energy received by earth per second = (Solar constant) R2 = 1.4 × 103 × 3.14 × (6.4 × 106)2 1.75 × 1017 W 73. A solar cooker used for heating water has solar panel of effective area 1 m2. Only 10% of the energy

received by the solar panel is utilized for heating the contents. Time taken by this solar cooker to heat 1 litre of water from 30°C to 80°C is nearly :

(A) 10 minutes (B) 15 minutes (C) 25 minutes (D) 40 minutes Ans. (C) Sol. Solar constant = 1.4 × 103 W/m2 (as found from Q.no. 72) Solar energy received per second = 1.4 × 103 × 1 = 1.4 × 103 J

Energy converted into heat per second = 3 2101.4 10 1.4 10 J100

Total heat required = 1 × 4200 × (80 – 30) = 2.1 × 105 J

Time taken =

5

22.1 10 3000s 25min.

2 601.4 10

74. Astronomers have discovered a planet orbiting and nearby star. It is estimated that the mass of this planet

is 16 times that of our earth and its density is one-fourth of the earth’s density. Assume that planets are spheres of uniform density. If your weight on the earth is 1000 N, then your weight on this planet would be:

(A) 5000 N (B) 1000 N (C) 2000 N (D) 4000 N Ans. (B)

Sol.

3

2 2

4G RGM 3gR R

4 G R3

4 G 'R'g' ' R'34g RG R3

....(1)

M' 16M

3

3R' ' 16R

3

3R' 16 4R

R' 4R

....(2)

From (1) & (2)

g' 1 4 1g 4

g' = g

Weight will remain same i.e. 1000 N

19

75. The absolute refractive index of medium P is 1.5. When light is incident on an interface between medium P and medium Q at an angle of incidence of 30° in medium P, the angle of refraction is where sin = 7/20. The speed of light in medium is given by :

(A) 1.4 × 108 m/s (B) 3.0 × 108 m/s (C) 2.5 × 108 m/s (D) 2.1 × 108 m/s Ans. (A)

Sol. nQP = 1/ 27 / 20

Q

P

nn

=

20 17 2

Qn1.5

= 107

nQ = 157

Now Q

cv

= 157

vQ = 83 10 715

= 1.4 × 108 m/s

* * * * *