CBSE Class 8 Science NSO Olympiad MCQs with Answers Set P

MENTAL ABILITY

Question. On dividing 2272 as well as 875 by 3digit number N, we get the same remainder. The sum of the digits of N is
(A) 10
(B) 11
(C) 12
(D) 13
Answer : A

Question. The value of (0.137 0.098)² - (0.137 0.098)²/0.137x0.098 is
(A) 0.039
(B) 0.235
(C) 0.25
(D) 4
Answer : D

Question. A group of students decided to collect as many paise from each member of the group as is the number of members. If the total collection amounts to ₹ 59.29, the number of members in the group is
(A) 57
(B) 67
(C) 77
(D) 87
Answer : C

Question. The average salary of all the workers in a workshop is ₹ 8000. The average salary of 7 technicians is ₹ 12000 and the average salary of the rest is ₹ 6000. The total number of workers in the workshop is
(A) 20
(B) 21
(C) 22
(D) 23
Answer : B

Question. The given question consists a set of figures. Figures P, Q, R and S constitute the Problem Set . There is a definite relationship between figures P and Q. Establish a similar relationship between figures R and S by selecting a suitable figure from the alternative that would replace the question mark (?) in figure (S).

Answer : C

Question. If 7 spiders make 7 webs in 7 days, then 1 spider will make 1 web in how many days?
(A) 1
(B) 7/2
(C) 7
(D) 49
Answer : C

Question. Armaan sells a bicycle to Abhay at a profit of 20%. Abhay sells it to Kabir at a profit of 25%. If Kabir pays ₹ 225 for it, the cost price of the bicycle for Armaan is
(A) ₹ 110
(B) ₹ 120
(C) ₹ 125
(D) ₹ 150
Answer : D

Question. Choose the correct mirrorimage of the given Figure (X), if the mirror is placed along PQ.

Answer : D

Question. Find out the wrong number in the series :
190, 166, 145, 128, 112, 100, 91
(A) 100
(B) 166
(C) 145
(D) 128
Answer : D

Question. The probability that a card drawn from a pack of 52 cards will be a diamond is
(A) 2/13
(B) 4/13
(C) 1/4
(D) 1/52
Answer : C

Question. In the given question, select a figure from amongst the four alternatives, which when placed in the blank space of figure (X) would complete the pattern.

 Answer : B

Question. If the compound interest on a sum for 2 years at 12(1/2)% per annum is ₹ 510, the simple interest on the same sum at the same rate for the same period of time is
(A) ₹ 400
(B) ₹ 450
(C) ₹ 460
(D) ₹ 480
Answer : D

DIRECTION (a - b) : The bargraph shows the sales of books (in thousand numbers) from six branches of a publishing company during two consecutive years 2009 and 2010.

Question a. Total sales of branches B1, B3 and B5 together for both the years (in thousand numbers) is
(A) 250
(B) 310
(C) 435
(D) 560
Answer : D

Question b. Total sales of branch B6 for both the years is what percent of the total sales of branch B3 for both the years?
(A) 68.54%
(B) 71.11%
(C) 73.17%
(D) 75.55%
Answer : C

Question. If a wire is bent into the shape of a square, then the area of the square is 121/4 sq. cm. When the wire is bent into a semicircular shape, then the area of the semicircle will be
(A) 22 cm²
(B) 44 cm²
(C) 77 cm²
(D) 154 cm²
Answer : C

SCIENCE

Question. If Sanjay stands one metre in front of a plane mirror, how far away from him will his image be?
(A) 2 m
(B) 1 m
(C) 0.5 m
(D) 4 m
Answer : A

Question. To finish off her cheesecake, Tissa adds a layer of whipped cream and a strawberry on top. There are two forces acting on the strawberry, an upward force from the cream and a downward force of gravity. If the force of gravity is larger than the force from the cream, then

(A) The strawberry will stay where it is
(B) The strawberry will sink into the cream
(C) The strawberry will fly from cream
(D) None of these.
Answer : B

Question. Which one of the following statements is not correct?
(A) The star closest to the poles appear to move less than those further away.
(B) The pole star is never seen in the southern hemisphere.
(C) People at the north pole see the pole star directly overhead.
(D) Polaris is the brightest star in the sky.
Answer : D

Question. The two common forces that are acting everywhere around us are
(A) Gravity and friction
(B) Gravity and magnetic force
(C) Friction and magnetic force
(D) Electrostatic force and gravity.
Answer : A

Question. When Raghav saw a film on space wars, there was something wrong about the explosion. What do you think it was ?
(A) The explosion was not loud enough.
(B) The explosion would not be heard.
(C) The explosion should have a lower pitch.
(D) The explosion should have a softer sound.
Answer : B

Question. Sometimes, when we pass under a tree covered with large number of leaves, we notice small patches of sunlight under it. These circular images are images of
(A) Tree
(B) Leaves
(C) Sun
(D) None of these.
Answer : C

Question. Read the following statements about the Earth carefully and choose the correct option.
(i) The earth revolves around its axis.
(ii) Rotation of the earth causes day and night.
(iii) Revolution is the movement of the earth around the sun.
(iv) The earth moves around the sun in a circular orbit.
(v) Different parts of the earth receive different amounts of sunlight.
(vi) The revolution of the earth causes day and night.
(A) (i), (ii) and (iii) are incorrect.
(B) (i), (iv) and (vi) are incorrect.
(C) (ii), (iv) and (vi) are incorrect.
(D) (iv), (v) and (vi) are incorrect.
Answer : B

Question. A boy was playing his drum, there were some beans placed near the drum. The harder he hit drum, the higher the beans jumped. What does the activity above show ?

(A) Sound is a form of energy.
(B) Beans have sound energy.
(C) The drumstick has sound energy.
(D) The boy transferred his potential energy to sound energy.
Answer : A

Question. Why do skis used in skiing on snow have large area ?
(A) To reduce the force of friction
(B) To reduce the pressure on the snow so that they do not sink in too far
(C) Both (A) and (B)
(D) None of these
Answer : B

Question. What is common among motion of the planets around the sun, blinking of traffic lights and motion of blades of a fan rotating at uniform speed ?
(A) Irreversible changes
(B) Chemical changes
(C) Periodic changes
(D) Undesired changes
Answer : C

Question. When Rakesh sings in the bathroom, his voice sounds much richer than normal. This is because
(A) Moisture in the air helps lubricate his vocal cord
(B) Sound waves reflected from the hard surfaces of the bathroom add richness to his voice
(C) Sound waves have a shorter distance to travel to his ear
(D) Water present in the bathroom absorbs all the unpleasant sounds.
Answer : B

Question. You cannot see a burning candle by using a bent pipe.

This is because
(A) Light gets bent along the pipe
(B) Light travels in straight line
(C) Light gets reflected
(D) Light gets absorbed
Answer : B

Question. Overhead cables need not be insulated ?
(A) Because air is normally not a good conductor
(B) Because air is mixture of gases
(C) Both (A) and (B)
(D) None of these
Answer : A

Question. A special bathroom mat keeps Rohan from slipping and falling in his bathroom. It does this by
(A) Reducing the amount of friction between his feet and the bathroom floor
(B) Keeping the bathroom floor free from moss
(C) Helping Rohan feet stay dry while he takes his bath
(D) Creating more friction under Rohan's feet as he steps on the mat.
Answer : D

Question. A small magnet Y is placed near a heavy magnet X as shown in the figure. How will the magnets move?

(A) Y will move away.
(B) Y will turn clockwise.
(C) Y will turn anti clockwise.
(D) X and Y, both will turn clockwise.
Answer : C

Question. Match column I with column II :
      Column I          Column II
(a) Iron nail          (i) Gaseous fuel
(b) L.P.G         .    (ii) Flame
(c) Candle           (iii) Combustible
(d) Coal              (iv) Noncombustible
(A) (a)(iii), (b)(i), (c)(ii), (d)(iv)
(B) (a)(iv), (b)(i), (c)(ii), (d)(iii)
(C) (a)(i), (b)(ii), (c)(iii), (d)(iv)
(D) (a)(iv), (b)(i), (c)(iii), (d)(ii)
Answer : B

Question. The three zones in a flame marked I, II and III are

Answer : D

Question. Aditya collects a copper wire, an aluminium wire, coal pieces and a pencil lead. He then takes a hammer and starts beating them. He observes that the coal pieces and pencil lead break whereas the copper wire & aluminium wire merely flatten because
(A) Metals are malleable
(B) Nonmetals are malleable
(C) Metals are brittle
(D) Nonmetals are not brittle
Answer : A

Question.

ZnSO₄ + Cu CuSO₄ + Fe CuSO₄ + Al FeSO₄ + Cu
The beakers in which displacement reaction takes place are
(A) Beaker A & B
(B) Beaker B & C
(C) Beaker C & D
(D) Beaker D & A
Answer : B

Question. Read the following statements carefully and identify X, Y and Z respectively.
(i) X reacts violently with cold water.
(ii) Y reacts with boiling water.
(iii) Z reacts with steam.
(A) Na, Mg, Zn
(B) Na, Zn, Fe
(C) Cu, Zn, Na
(D) Zn, Cu, Na
Answer : B

Question. Polythene and PVC are the examples of ____ and bakelite and melamine are the examples of ____
(A) Thermoplastics, plastics
(B) Thermosetting plastics, plastics
(C) Thermosetting plastics, thermoplastics
(D) Thermoplastics, thermosetting plastics.
Answer : D

Question. Match column A with column B :
       Column A                        Column B
(a) Polythene            (i) Natural polymer from plants
(b) Polymers            (ii) Small units of making fibre
(c) Cotton                (iii) Bad conductor of heat and electricity
(d) Plastics              (iv) Fibre obtained from moth
(e) Silk                    (v) Chokes respiratory system on burning
(A) (a)(ii), (b)(v), (c)(iii), (d)(i), (e)(iv)
(B) (a)(v), (b)(ii), (c)(i), (d)(iii), (e)(iv)
(C) (a)(iv), (b)(v), (c)(ii), (d)(i), (e)(iii)
(D) (a)(iii), (b)(i), (c)(v), (d)(iv), (e)(ii)
Answer : B

Question. Which of the following statements are true?
(1) Plastics do not corrode easily.
(2) Plastics are biodegradable in nature.
(3) Thermosetting plastics can be remoulded again and again upon heating.
(4) Plastics are thermal insulators.
(A) 1 and 2
(B) 2 and 3
(C) 3 and 4
(D) 1 and 4
Answer : D

Question. The figure shown here represents

(A) Nitrogen fixation
(B) Fermentation
(C) Decomposition
(D) Photosynthesis
Answer : C

DIRECTION: Read the following paragraph and answer Q. nos. a and b.
Microbial diseases that can spread from an infected person to a healthy person through air, water, food or physical contact are called X. There are some insects and animals that are Y of disease – causing microbes. Housefly is one example.

Question a. What does X represent to ?
(A) Noncommunicable diseases
(B) Communicable diseases
(C) Congenital diseases
(D) Both (B) and (C).
Answer : B

Question b. What does Y represent to ?
(A) Pathogens
(B) Parasites
(C) Carriers
(D) Symbionts.
Answer : C

Question. Which of the following is correct pairing of the organelle with its function ?
      Organelles                      Functions
(A) Lysosome                Synthesizes protein
(B) Ribosome                Helps in osmoregulation
(C) Mitochondrion         Synthesizes ATP
(D) Nucleus                  Traps solar energy.
Answer : C

Question. Given below is the comparison between plant cell and animal cell. Which option is incorrect ?

Answer : B

Question. The given figure represents the position of various endocrine glands in human body. Select an option with correctly labelled parts.

Answer : B

Question. When fertilization does not occur, the uterine lining breaks down and blood flows out of the body through vagina. What does this process called ?
(A) Menarche
(B) Gestation
(C) Menstruation
(D) Menopause.
Answer : C

Question. Which of the following animals is not endemic to India ?
(A) Liontailed macaque
(B) Snow leopard
(C) Flying squirrel
(D) Sloth bear.
Answer : B

Question. Match the following agricultural tasks with their respective implements and select the correct option.
Agricultural tasks             Implements
(a) Tilling                        (i) Combine
(b) Sowing                     (ii) Trowel
(c) Irrigation                  (iii) Seed drill
(d) Weeding                  (iv) Plough
(e) Harvesting               (v) Sprinkler
(A) (a)(v), (b)(ii), (c)(iv), (d)(i), (e)(iii)
(B) (a)(iv), (b)(iii), (c)(v), (d)(ii), (e)(i)
(C) (a)(iii), (b)(iv), (c)(v), (d)(i), (e)(ii)
(D) (a)(ii), (b)(iii), (c)(v), (d)(iv), (e)(i)
Answer : B

Question. Which one of the following steps is not followed in storage process of food grains ?
(A) Water is sprinkled on the stored food grains from time to time.
(B) Food grains are stored in well ventilated godowns.
(C) Pesticides are sprayed over the grains.
(D) Periodic inspection of the stored grains.
Answer : A

Question. Which of the following is not an asexual reproduction?

Answer : B

Question. Analyse the given data on the average rate of growth in height of boys and girls within different age groups. Select the correct interpretation(s) made on the basis of tabular data. 
Interpretations :
(i) Girls grow taller than boys.
(ii) Girls and boys have different set of hormones which control their growth.
(iii) Girls grow faster than boys.
(iv) Height of girls and boys depends on the genes inherited from their parents.

(A) (i) & (iii)
(B) (ii) & (iii)
(C) (iv) only
(D) (i), (iii) & (iv).
Answer : B