CBSE Class 10 Science NSO Olympiad MCQs with Answers Set G

LOGICAL REASONING

Question. How many pairs of letters are there in the word SUPPOSITION which have as many letters between them in the word as in the English alphabet?
A. 4
B. 6
C. 7
D. More than 7
Answer : D

Question. Which of the following figures will complete the given figure matrix?

Answer : A

Question. Which of the following options satisfies the same conditions of placement of dots as in Fig. (X)?

Answer : B

Question. Read the following information and answer the question that follows.
(i) Four persons P, Q, R and S eat mango, apple, orange or guava from Monday to Thursday. No two persons eat the same fruit on a day. Each of them eats only one fruit on a day and does not repeat it any other day.
(ii) Neither R nor S eats orange or guava on Tuesday.
(iii) Q eats apple on Wednesday.
(iv) P eats guava on Monday.
(v) R does not eat mango on Thursday.
(vi) S eats apple on Monday.
Which fruit does R eat on Monday?
A. Apple
B. Mango
C. Guava
D. Orange
Answer : B

Question. Find the missing number, if a certain rule is followed either row wise or column wise.

A. 16
B. 21
C. 24
D. 8
Answer : A

Question. In the given Venn diagram, square represents graduates, triangle represents self-employed people and circle represents the females.
Which of the following numbers represent males who are graduates and self-employed?

A. 4
B. 5
C. 1
D. 7
Answer : D

Question. There are seven figures, the first and last of which are unnumbered and the remaining five are numbered as 1, 2, 3, 4 and 5. These seven figures form a series.
However, one of the five numbered figures does not fit into the series. Select the figure that does not fit into the series.

A. 1
B. 4
C. 5
D. 2
Answer : D

Question. Study the given information and answer the following question.
(i) 'P × Q' means 'P is father of Q'.
(ii) 'P ÷ Q' means 'P is daughter of Q'.
(iii) 'P - Q' means 'P is sister of Q'.
(iv) 'P + Q' means 'P is husband of Q'.
Which of the following indicates X is mother of W?
A. W – Y ÷ X + Z
B. W ÷ Y – X ÷ Z
C. W + Y ÷ X – Z
D. W – Y ÷ X – Z
Answer : D

Question. Count the number of triangles and rectangles respectively in the given figure.

A. 22 and 8
B. 20 and 9
C. 21 and 9
D. None of these
Answer : C

Question. Select the correct water image of Fig. (X).

Answer : A

SCIENCE

Question. The diagram shows a circuit containing three light bulbs. The circuit is connected to a 12 V battery. What is the current I flowing across 6 W light bulb?

A. 1 A
B. 2 A
C. 0.67 A
D. 0.92 A
Answer : C

Question. The time period of a satellite of earth is 5 hours. If the separation between the earth and the satellite is increased to 4 times the previous value, then the new time period will become
A. 10 hours
B. 80 hours
C. 40 hours
D. 20 hours.
Answer : C

Question. An ultrasound is used to measure the distance from the ship to the sea bed. A cathode ray oscilloscope (c.r.o.) placed in the ship traces a pulse sent from the ship and reflected pulse that returns. The time-base setting for the x-axis is 50 ms per division.
The speed of ultrasound in water is 1500 m s^–1. Find the distance from the ship to the sea bed.

A. 450 m
B. 600 m
C. 900 m
D. 750 m
Answer : A

Question. Let the refractive index of a denser medium with respect to a rarer medium be μ₁₂ and its critical angle θ_C. At an angle of incidence A when light is travelling from denser medium to rarer medium, a part of the light is reflected and the rest is refracted and the angle between reflected and refracted rays is 90°. What is the relation between angle A and θ_C?
A. tan A = sin θ_C
B. sec A = cos θ_C
C. sin A = tan θ_C
D. cos A= sec θ_C
Answer : A

Question. A variable force F acting on a particle of mass m kg is indicated by the force-time graph as shown. The change in momentum of the particle over the time interval from 0 to 6 s is

A. 4 kg m s^–1
B. 6 kg m s^–1
C. 10 kg m s^–1
D. 12 kg m s^–1
Answer : B

Question. Read the given statements and select the correct option.
Statement 1 : Focal length of a spherical mirror depends on distances of object and image from the mirror.
Statement 2 : Focal length of a spherical mirror is equal to the radius of curvature of spherical mirror.
A. Both statements 1 and 2 are true and statement 2 is the correct explanation of statement 1.
B. Both statements 1 and 2 are true but statement 2 is not the correct explanation of statement 1.
C. Statement 1 is true but statement 2 is false.
D. Both statements 1 and 2 are false.
Answer : D

Question. Which of the following statements are incorrect?
(i) A typical solar cell can produce about 0.5 W electricity when exposed to the Sun.
(ii) One atomic mass unit (u) is equivalent to about 931 MeV of energy.
(iii) The hydrogen bomb is based on thermonuclear fission reaction.
(iv) Solar cells are less expensive and highly efficient.
(v) India receives solar energy equivalent to 500 trillion kWh per year.
A. (i), (ii) and (iii) only
B. (iii) and (iv) only
C. (i), (iii), (iv) and (v) only
D. (ii), (iv) and (v) only
Answer : C

Question. An apartment block receives water from a nearby reservoir. A pump is necessary to lift the water into a storage tank at the top of the building. The acceleration due to gravity is 10 m s^–2 

How much energy does the pump supply to lift each kilogram of water into the tank?
A. 50 J
B. 100 J
C. 400 J
D. 500 J
Answer : B

Question. Figure shows PQ, QR, RS and SP, the walls of room PQRS, each measuring 8 m. The wall PQ has a full length plane mirror. A camera is placed at M the mid point of wall SR. In order to take clear image of the point R, the camera should be focused at

A. 4 m
B. 8 m
C. 16 m
D. More than 16 m.
Answer : D

Question. A man in a lift ascending with an acceleration throws a ball vertically up with a velocity u and catches it after time t₁. Afterwards when the lift is descending with the same acceleration, the man again throws a ball vertically up with the same velocity and catches it after time t₂. The velocity of projection of ball is

Answer : B

Question. Which of the following statements are correct?
(i) A metallic wire carrying an electric current has associated with it a magnetic field whose direction is given by Maxwell's corkscrew rule.
(ii) The pupil of eye acts like a variable aperture whose size can be varied with the help of cornea.
(iii) A dc motor is a device which works on the basis of electromagnetic induction.
(iv) Earth wire is used as a safety measure to ensure that any leakage of current to a metallic body does not give any severe shock to a user.
(v) Hypermetropia is an eye defect which arises due to elongation of eye ball.
A. (i), (iii) and (iv) only
B. (ii), (iii) and (v) only
C. (i) and (iv) only
D. (i), (ii), (iv) and (v) only
Answer : C

Question. The masses of the wires of copper are in the ratio of 1:3:5 and their lengths are in the ratio of 5:3:1. The ratio of their electrical resistance is
A. 1:2:3
B. 1:3:5
C. 125:15:1
D. 1:25:125
Answer : C

Question. The given reaction occurs in a car battery when it is used to produce electricity.
Pb + PbO₂ + 2H₂SO₄ → 2PbSO₄ + 2H₂O
Which of the following statements are incorrect about this reaction?
I. Pb is acting as an oxidising agent.
II. H₂SO₄ is acting as a reducing agent.
III. The reaction is a precipitation reaction.
IV. PbO₂ oxidises Pb to PbSO₄.
A. III and IV only
B. I and II only
C. I and III only
D. I, II, III and IV
Answer : B

Question. A few chemical properties of three metals X, Y and Z are summarised in the given table

The methods which can be used to extract X, Y and Z from their ores are respectively
A. Electrolysis, reduction with carbon and heating alone
B. Heating with carbon, aluminothermy and electrolysis
C. Calcination, aluminothermy and roasting 
D. Heating the metal oxide, heating with carbon and electrolysis.
Answer : A

Question. Which of the following options shows the correct arrangement of different substances with increasing pH values?
A. Ammonium hydroxide, magnesium hydroxide, lactic acid and sulphuric acid
B. Sulphuric acid, lactic acid, sodium hydroxide and ammonium hydroxide
C. Potassium hydroxide, calcium hydroxide, acetic acid and hydrochloric acid
D. Hydrochloric acid, acetic acid, ammonium hydroxide and potassium hydroxide
Answer : D

Question. Mitaali, a class 10 student wanted to study the speed of reactions of different acids with zinc metal. For this, she conducted the following experiments using zinc metal in excess.

She measured the volume of H₂ gas produced at regular time intervals and summarised her results in a graphical form.
Which of the following graphs best represents the results obtained in experiments I, II and III?

Answer : B

Question. The melting and boiling points of four different substances are given in the table.

All the substances are heated from 0 °C to 100 °C.
The substance which will change from solid to liquid and the substance which will change from liquid to gas are respectively
A. Q and P
B. P and Q
C. R and S
D. P and S.
Answer : B

Question. Titanium chloride (TiCl₃) is used as a catalyst in plastic industry. How many chlorine atoms are there in 38.6 g of TiCl₃?
[Given : Atomic mass of Ti = 48 u, Cl = 35.5 u]
A. 18.06 × 10²³
B. 3.12 × 10²³
C. 4.5 × 10²³
D. 1.5 × 10²³
Answer : C

Question. The given part of the modern periodic table shows positions of elements a to j.

Fill in the blanks by choosing an appropriate option.
Element i resembles sodium in properties and element ii belongs to the same group as nitrogen. The formula of the hydride of g is iii . The formula of compound formed between b and c is iv while the formula of compound formed between e and g is v .
     i    ii       iii       iv      v
A. h    g     Hg     bc₂    e₂g
B. a     j     H₂g   bc₃    eg
C. b     j     Hg     b₂c    eg₂
D. h     i     Hg₂   bc      eg
Answer : B

Question. Match column I with column II and select the correct option from the given codes.
              Column I                              Column II
(a) C₂H₅OH → CH₃COOH       (i) Conc. H₂SO₄, 170 °C
(b) C₂H₅OH → CH₂ CH₂         (ii) H₂, Ni
(c) CH₄ → CH₃Cl                    (iii) Alk. KMnO₄
(d) CH₂ = CH₂ → CH₃CH₃     (iv) Cl₂, sunlight
A. (a) - (i), (b) - (iii), (c) - (ii), (d) - (iv)
B. (a) - (iv), (b) - (iii), (c) - (ii), (d) - (i)
C. (a) - (i), (b) - (iv), (c) - (iii), (d) - (ii)
D. (a) - (iii), (b) - (i), (c) - (iv), (d) - (ii)
Answer : D

Question. Rohit and Mayuri conducted two experiments to study the types of chemical reactions as shown in the given figures.

They recorded their observations as :
I. In experiment 1, yellow residue is left behindwhile in experiment 2 reddish brown solid is left behind.
II. In both experiments, two different gases were given out.
III. The colourless gas evolved in experiment 1 extinguishes the glowing splint while the gas evolved in experiment 2 turns green solution of acidified KMnO4 orange.
IV. X is reddish brown gas while gases Y and Z both have burning sulphur smell.
The incorrect observation(s) is/are
A. IV only
B. III only
C. I and III only
D. II and III only.
Answer : B

Question. Schematic representation of three atoms X, Y and Z is given as

Which of the following statements is/are correct?
I. X, Y and Z are isotopes.
II. X and Z have the same valency.
III. The increasing order of atomic numbers is X < Z < Y.
IV. X, Y and Z have stable electronic configurations.
A. II and III only
B. I and II only
C. II and IV only
D. None of these
Answer : A

Question. Study the given Venn diagram carefully.

Which of the following colloidal systems correctly represents 1, 2 and 3?
            1                            2                        3
A. Fog                      Soap lather             Smoke
B. Hair cream           Milk                         Foam
C. Starch solution    Dust fumes              Mist
D. Pearls                 Coloured glasses    Cheese
Answer : C

Question. The given apparatus is used to study the diffusion of a number of gases at the same temperature and pressure.
Which of the following pairs of gases would diffuse into the vacuum at the same speed?

[Given : Atomic mass of H = 1 u, C = 12 u, N = 14 u,
S = 32 u, O = 16 u]
A. NH3 and H₂
B. CO and SO₂
C. CO and N₂
D. NH₃ and N₂
Answer : C

Question. Refer to the given figures showing bones of wings of two animals X and Y. These wings are Z structures.
Select the option that correctly identifies X, Y and Z.

      X        Y                   Z 
A. Bat     Bird          Analogous
B. Bat     Insect       Homologous
C. Bird    Bat           Homologous
D. Bird    Insect       Analogous
Answer : A

Question. Refer to the given diagram

Identify Q, R, S and T and select the correct option.
A. R has hollow bones and possesses hair whereas S has cartilaginous endoskeleton and lacks hair.
B. The skin of Q is non-glandular and keratinised while the skin of T is glandular and non-keratinised.
C. In R, muscular partition called diaphragm is present between thorax and abdomen while in S, diaphragm is absent.
D. Both Q and T have four chambered heart with two atria and two ventricles.
Answer : C

Question. What does the given flow chart represent?
Producers → Herbivores → Carnivores
20 units         2 units              0.2 units
A. Unidirectional energy flow
B. Lindeman’s law
C. Biomagnification
D. Both A and B
Answer : D

Question. Refer to the given graph depicting reaction velocity of two enzymes X and Y. Identify enzymes X and Y and select the correct statement regarding them.

A. Y converts fats to fatty acid and glycerol while X protects the lining of stomach from the action of HCl.
B. X converts proteins into peptones while Y converts proteins into dipeptides.
C. X kills the bacteria present in the food and converts inactive propepsin into active pepsin.
D. X converts starch into maltose while Y converts fat into fatty acid and glycerol
Answer : B

Question. Neha set-up an experiment as shown here.
She left the set-up undisturbed for some time. Which of the following statements correctly describes the appearance of the potato tuber after 3 hours?

A. The bottom half would be flaccid while the top half would be turgid.
B. The bottom half would be turgid while the top half would be flaccid.
C. It would have uniform turgidity.
D. None of these
Answer : C

Question. Which of the following statements is incorrect?
A. A pyramid of energy can never be inverted.
B. Use of high temperature for waste disposal is called land filling.
C. Food chain shows unidirectional flow of energy and proceeds in a progressive straight line.
D. All of these
Answer : B

Question. Which of the following statements is incorrect?
A. Placenta allows exchange of materials between mother and fetus.
B. The fetal part of the placenta consists of the cells of the chorion which produce projections called chorionic villi.
C. Antibody cannot cross the placenta from mother to fetus.
D. Placenta secretes pregnancy hormones required for supporting fetal growth and metabolic changes in mother during pregnancy.
Answer : C

Question. Refer to the given pedigree chart showing inheritance of fused ear lobe trait in three generations of a family.
Select the option that correctly depicts the genotypes of I-2, II-4 and III-2.

    I-2       II-4     III-2
A. PP      PP     Pp
B. Pp      Pp     Pp
C. pp      Pp     Pp
D. PP     Pp     Pp
Answer : C

Question. Refer to the given figures representing requirement of duration of light (◻) and dark (◼) periods by plants X and Y for flowering. Select the correct option regarding them.

A. X could be lettuce while Y could be Dahlia.
B. Plant Y can flower in complete darkness if supplied with exogenous nutrients.
C. Interruption of light periods by dark periods inhibits flowering in plant X.
D. X could be sugarcane while Y could be wheat.
Answer : D

Question. Refer to the given flow chart and select the correct statement regarding W, X, Y and Z.

A. W could be syphilis whereas Z could be chicken pox.
B. W could be AIDS whereas Y could be dengue.
C. Y could be kala azar whereas Z could be sleeping sickness.
D. X could be gonorrhoea whereas Y could be diabetes.
Answer : B

Question. Refer to the given dichotomous key and select the correct option regarding P, Q, R, S and T.
I. (a) Genetic material is not enclosed in nucleus. – Go to II
(b) Genetic material is enclosed in nucleus. – Go to III
II. (a) Lacks cell wall. – P
(b) Possesses cell wall. – Q
III. (a) Unicellular organism – R
(b) Multicellular organism – Go to IV
IV. (a) Plant body is sporophytic and water is required for fertilisation. – S
(b) Plant body is sporophytic and water is not required for fertilisation. – T
A. P is motile whereas Q is non-motile.
B. R could be yeast or Chlamydomonas.
C. Both S and T produce seeds for propagation of their species.
D. S could be Adiantum whereas T could be Riccia
Answer : B

ACHIEVERS SECTION

Question. Refer to the given paragraph where few words/phrases have been italicised.
There are three kinds of blood vessels in humans. 
Arteries are thick walled vessels that carry deoxygenated blood (except pulmonary artery) away from heart. 
Veins are thin walled, vessels that bring oxygenated blood (except pulmonary vein) back to the heart.
Capillaries are thin walled vessels that are permeable to water and dissolved substances.
Select the correct option regarding it.
A. Thick and thin should be interchanged.
B. Oxygenated and deoxygenated should be interchanged.
C. Pulmonary artery should be replaced with carotid artery whereas pulmonary vein should not be replaced as it is correctly mentioned.
D. Permeable should be replaced with impermeable.
Answer : B

Question. Refer to the given graph representing hormonal levels during a normal menstrual cycle in a female. Identify the ovarian hormones X and Y and select the correct statement regarding them.

A. If hormone Y is insufficiently produced in a female then uterine lining might not be sufficiently stable to support an implanted embryo.
B. Level of hormone Y is very high during menstrual phase of menstrual cycle in a female.
C. Hormone X is secreted by corpus luteum under the influence of follicle stimulating hormone of anterior pituitary gland.
D. Hormone X stimulates transformation of a primary follicle of ovary into Graafian follicle.
Answer : A

Direction (Q. No. a and b) : Refer to the given passage and answer the following questions.
When alcohols react with carboxylic acids in the presence of concentrated sulphuric acid, compounds with fruity smell called esters are formed. Also, alcohols on oxidation in the presence of acidified K₂Cr₂O₇ form carboxylic acids.

Question a. If third member of alcohol family (homologous series) undergoes esterification reaction with second member of carboxylic acid family then, the name of ester formed and its formula will be respectively
A. Ethyl propanoate, CH₃CH₂COOCH₂CH₃
B. Propyl ethanoate, CH₃COOCH₂CH₂CH₃
C. Ethyl butanoate, CH₃CH₂CH₂COOCH₂CH₃
D. Ethyl ethanoate, CH₃COOCH₂CH₃.
Answer : B

Question b. C₂H₅OH on oxidation with acidified K₂Cr₂O₇ gives CH₃COOH. Which of the following statements is/are correct regarding these two compounds?
I. They both react with sodium metal to evolve a combustible gas.
II. They both react with NaHCO₃ to evolve a gas which turns lime water milky.
III. They both turn blue litmus red.
A. I and II only B. II only
C. I only D. I, II and III
Answer : C

Question. Column I shows certain current distribution and column II shows the variation of magnitude of magnetic field B with distance x as one moves along x-axis from point O. Match column I with column II and select the correct option

      I   II III
A. Q  P  R
B. Q  R  P
C. R  Q  P
D. P  Q  R
Answer : B