Nso Level2 Class 8 Set 2

DO NOT OPEN THIS BOOKLET UNTIL ASKED TO DO SO Roll No. Total Questions: 50

Time: 1 hr.

CLASS

8

SET-2

sof national science olympiad

Level-2 Guidelines for the Candidate 1.

You will get additional ten minutes to fill up information about yourself on the OMR Sheet, before the start of the exam. 2. The Question Paper comprises two sections, Science (45 Questions) and Achievers Section (5 Questions). Each question in Achievers Section carries 3 marks, whereas all other questions carry one mark each. 3. All questions are compulsory. There is no negative marking. Use of calculator is not permitted. 4. Write your Name, Roll No. and Class clearly on the OMR Sheet and do not forget to sign it. 5. There is only one correct answer. Choose only ONE option for an answer. 6. To mark your choice of answer by darkening the circles in the OMR Sheet, use an HB Pencil or a Blue/Black ball point pen only. E.g. Q.16 : Raj goes to school on a bicycle. Which of these safety rules he should follow? A. He should give signals before taking turns. B. He should keep to the right of the road. C. He should cross the road by using zebra crossing. D. All of these. As the correct answer is option A, you must B C D 16. A darken the circle corresponding to option A in the OMR Sheet. 7. Rough work should be done in the blank space provided in the booklet. 8. Return the Question Paper and OMR Sheet to the invigilator at the end of the exam.

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science 1.

The given Figure shows a uniform beam balanced at its centre point which has an object weighing 30 N placed 20 cm from its midpoint on the left.

The beam will be balanced by applying a force of

A. B. C. D.

30 N downwards, 10 cm from centre on left. 30 N downwards, 30 cm from centre on left. 20 N upwards, 20 cm from centre on right. 20 N downwards, 30 cm from centre on right.

2.

Which of the following statements is correct.



A. B. C.



D.

3.

A force of 5 N acts on a area of 50 cm2 then pressure in pascal will be



A. B. C. D.

4.

It is difficult for a horse to pull the cart during first few steps because.



A. B. C.



D.

5.

Read the given statements and mark correct option.

Rolling friction is greater than sliding friction Kinetic friction is less than static friction To increase the friction objects are given streamlined shape Normal force is equal to maximum dynamic friction

1000 Pa 0.1 Pa 10 Pa 100 Pa

No friction acts after body comes in motion Limiting friction is greater than dynamic friction Air friction is greater during first few steps of motion. Sliding friction is greater than rolling friction

Statement 1 : An object appears to be heavier at poles than at equator Statements 2 : The gravitational force at the poles is less than at equator.

A.



B.



C. D.

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Both statements 1 and 2 are true and statement 2 is correct Explanation of statement 1 Both statements 1 and 2 are true but statement 2 is is not the correct Explanation of statement 1. Statement 1 is true and statement 2 is false. Both statements 1 and 2 are false

6.

Match column I with column II and select correct options from the given codes.

(p) (q) (r) (s) A. B. C. D.

Column I Column II 1 atm (i) 760 torr 1 Pascal (ii) 1.013 bar 760 mm of Hg (iii) N m–2 Dyne cm–2 (iv) 10–1Nm–2 P(i), (ii) Q(iv) R(iii) S(ii), (iii) P(i), (ii) Q(ii), (iv) R(iii) S(iv) P(i), (ii) Q(iii) R(i), (ii) S(iv) P(iv) Q(i) R(ii) S(iii)

7.

Which of the following is/are the application(s) of ultrasonic waves



A. B. C. D.

8.

The diagram below is of a human ear. Identify the parts P, Q, R and S suspectively.



A. B. C. D.

9.

Fill in the blanks by choosing correct option. The (i) of a sound, depends on rapidity of its

Detect flaws in metal structures Detect kidney stone. Detection of air craft, submarines etc. All of these

Pinna, Auditory canal, Cochlea, Auditory nerve Pinna , Cochlea, Auditory, Canal, Auditory nerve Pinna, Auditory nerve, Cochlea, Auditory canal Pinna, Eardrum, Auditory Nerve, Auditory canal

(ii) . The (iii) of vibrating body is number of vibrations per unit time. The (iv) of a sound dependson the amplitude of vibrations. A. B. C. D.

(i) Pitch Pitch Pitch Frequency

(ii) Frequency Frequency Vibrations Vibrations

(iii) Loudness Vibrations Frequency Loudness

(iv) Vibrations Loudness Loudness Pitch

10. In the solution of water, when current is passed, the hydrogen and oxygen ions separates. The hydrogen ions gets accumulated on the cathode. The reason for deposit on a negative electrode is A. Hydrogen ion in positively charged B Hydrogen is negative charge C. It is characteristic of acidulated of water. D. None of these. Class-8 | Level 2

11. Which of the following statements is incorrect.

A.



B.



C.



D.

Electrons move from positive electrode to negative electrode. A positively charged particle has higher electric potential than a negatively charged particle Pure water can be used as an electrolyte in the process of electrolysis The byproducts of electrolyte of impure water are hydrogen and oxygen.

17. ________ refracts light that enters the eye and helps to focus light into the retina.

A. C.

Sclera Cornea

B. D.

Aqueous humour Optic lens

18. A lens forms a blurred image of an object on a screen. To focus image on screen,

12. In the process of electrolysis. If electric current is passed through a copper sulphate solution the copper deposits on electrode connected to _________.

A. B. C. D.

Positive terminal of the battery Negative terminal of the battery Any one terminal either positive or negative None of these

13. When we remove a woollen cloth in dark, we will see spark and hear a cracking sound these are due to

A. B. C. D.

Static electricity Dynamic electricity Earthing Atmospheric electricity

A. C.

Epicenter Seismic or fault zone

B. D.

Stress None of these

15. The diagram shows a ray of light reflected at a plane mirror. Which pair of the angle of incidence and angle of reflection is correct.

A. B. C. D.

Angle of Incidence 75 15 30 15

Angle of Reflection 75 15 30 30

16. A ray of light is incident on a horizontal plane mirror at an angle of incidence 60°. At what angle should a second plane mirror be inclined to horizontal mirror so that reflected ray from the horizontal mirror is reflected by second mirror horizontally?

A. C.

60° 75°

Class-8 | Level 2

A.



B. C. D.

B. D.

30° 90°

Use a lens of longer focal length of same position Move an object towards the lens and screen. Move the screen away from the lens Use a smaller object at same position.

19. The axis of the earth is inclined to the orbital plane at an angle of ________.

14. The point from which the Earthquake waves originate is known as



A. C.

66.5° 65.6°

B. D.

23.5° 22.5°

20. Pickles are stored in a glass container instead of metal container because A. Of acidic nature of pickles B. Of basic nature of pickles C. They are neutral in nature D. Does not depend on the material of the container. 21. Inexhaustible natural resources are

A. B. C. D.

Unlimited in quantity in nature Limited in quantity in nature Not exhausted by human activities Both A and C.

22. Read the given statements and mark the correct option.



Statement 1 : Cooking oil and wood do not catch fire on their own at room temperature. Statement 2 : Combustible substance cannot catch fire or burn as long as its temperature is higher than its ignition temperature. 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 and statement 2 is false. D. Statement 1 is false and statement 2 is true

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23. Match the items given in column I with the items given in column II. (a) (b) (c) (d) A. B. C. D.

Column I Column II Nylon (i) Carpets Rayon (ii) Blankets Polyester (iii) Ropes Acrylic (iv) Film (a) - (iv), (b) - (ii), (c) - (iii), (d) - (i) (a) - (ii), (b) - (i), (c) - (iv), (d) - (iii) (a) - (i), (b) - (iii), (c) - (ii), (d) - (iv) (a) - (iii), (b) - (i), (c) - (iv), (d) - (ii)

24. The only metal which exists in liquid state at room temperature is

A. C.

Oxygen Sulphur

B. D.

Mercury Sodium

25. Nowadays, which of the following petroleum products is used in metalling of the roads?

A. C.

Bitumen Coke

B. D.

Coal tar Coal

26. The rubbing surface of safety match contains

A. B. C. D.

White phosphorus Powdered glass and little red phosphorus Antimony trisulphide and potassium chlorate White phosphorus and little red phophorus.

27. Which of the following is used for non-stick coating on cookwares?

A. C.

Teflon Aluminium

B. D.

Polyester PVC

28. Vineet kept a copper vessel in the humid air for long. He observed

A.



B. C. D.

Green coating due to the formation of Cu(OH)2 and CuCO3 Black coating due to the formation of CuO No change in the copper vessel Green coating due to the formation of CuS.

29. Select the incorrect statement.

A.



B. C.



D.

CNG is less polluting, thus it is used as a fuel for transport vehicles. Petroleum is also called as 'black gold'. Coal when burnt in air produces mainly carbon dioxide gas. Naphthalene balls are obtained from coal tar.

30. To compare tensile strength of fibre – cotton and nylon, Kritika took 50 cm of each fibre and tied one end of it with the hook of an iron stand one by one. Weights of 50 g and 100 g were tied on the other end of the thread . What did she observed?

4



A.



B.



C.



D.

100 g weight tied with cotton thread will break readily while 50 g weight tied with nylon thread will not break. 50 g weight tied with cotton thread will break readily while 50 g weight tied with nylon thread will not break. 100 g weight tied with cotton thread will break readily while 100 g weight tied with nylon thread will not break. 50 g weight tied with cotton thread will break readily while 100 g weight tied with nylon thread will not break.

31. Cultivation of crops involves several activities undertaken by farmers over a period of time. These activities called agricultural practices require different agricultural implements. Select the correct sequence of using different implements for various agricultural practices.

A.



B.



C.



D.

Seed drill, Compost, Trowel, Plough, Sickle, Jute bags Cultivator, Seed drill, Biofertilisers, Drip irrigation, Trowel, Harvester, Silos. Hoe, Rahat system, NPK-fertilisers, Seed drill, Graneries, Combine Moat, Seed drill, Compost, Combine 2, 4-D, Sickle, Jute bags.

32. Use the given dichotomous key and select the correct option.

I. (a) They are simple plant-like organisms, that have cell wall and chlorophyll – Go to II (a) (b) They are link between living and non-living – Go to II (b) and III (b) II. (a) They make their own food by photosynthesis – Go to III (a) (b) They use energy of host cell for reproduction – P III. (a) They can be unicellular or multicellular – Q (b) R infect bacteria and S affects vegetables. P Q R S A. Rhizopus Fucus Adeno Tobacco virus mosaic virus B. Giardia Agaricus Penicillium Vibrio Cholerae C. Trypanosoma Laminaria Influenza Lacto- virus bacillus D. Virus Spirogyra Bacterio- Tobacco phage mosaic virus

Class-8 | Level 2

33. Read the given statements each with one or two blanks in it.









P.

(i) provides support and strength to plant cell. Q. In plants, (ii) are called dictyosomes. R. (iii) are non-membranous cell organelle and contains (iv) as main constituent. S. (v) are absent in animal cell and (vi) help in osmoregulation. Select the option which correctly fills some of the blanks in these statements. A. B. C. D.

(ii) Used for producing biogas by decomposing animal waste. (iii) Causes anthrax disease in humans and cattle. A. Protozoa B. Bacteria C. Virus D. Fungi

38. Sakshi wants to see microscopic view of the organelle which serves as transport channels for materials to pass through and is involved in protein synthesis. Which labelled part will her teacher focus to make a microscopic view of the organelle ?

(i)-Cell membrane, (iii)-Ribosomes, (iv)-RNA (ii)-Golgi complex, (iv)-RNA, (vi)-Vacuoles (iii)-Ribosome, (iv)-DNA, (v)-Plastids (i)-Cell wall, (iv)-Protein, (vi)-Mitochondria

34. Match column I (agricultural practices) with column II (words to unscramble) and select the correct option from the given codes. Column I Column II (i) The process of loosening (a) HSERTNGIH and turning of soil (ii) Separation of grain from (b) EDINWEG harvested crop (iii) Process of removing (c) ILITNGL unwanted plants from the field (iv) Separation of grain from (d) WNNOGNIW chaff A. (i)-(c), (ii)-(a), (iii)-(b), (iv)-(d) B. (i)-(d), (ii)-(b), (iii)-(a), (iv)-(c) C. (i)-(b), (ii)-(a), (iii)-(c), (iv)-(d) D. (i)-(a), (ii)-(b), (iii)-(d), (iv)-(c)



A. C.

P R

B. D.

Q S

39. Read the given statements and select the correct option.

Statement 1 : Nucleus of the cell can be compared to brain in animals.



Statement 2 : Nucleus contains genes responsible for transmission of characters from parents to offspring.



A.

35. Atlas 66, a wheat variety having high protein content has been developed by _______.



B.





C. D.

A. B. C. D.

Genetic modification Hydridisation Green revolution Biofortification

Both statements 1 and 2 are true and statement 2 is the correct explanation of statement 1. Both statements 1 and 2 are true but statement 2 is not the correct explanation of statement 1. Statement 1 is true but statement 2 is false. Both statements 1 and 2 are false.

40. Study the given classification chart carefully and identify the categories of threatened species.

36. What are the consequences of indiscriminate cutting down of trees?

A. B.



C. D.

It results in lowering rainfall It exposes less fertile layer of soil by eroding humus rich top soil. It reduces water absorption capacity of soil. All of these.

37. Microorganisms are both useful and harmful to the mankind. Read the given statements and identify the associated microbe.

(i)

Used for curdling of milk to make cheese.

Class-8 | Level 2

Threatened species

Species not likely to survive and will soon become extinct. J

Species likely to move to endangered category in near future.

J A. Extinct in wild

K

K Vulnerable

Species exist in small number and is localised to certain geographical area. L L Rare

5

B. Critically Endangered endangered C. Endangered Vulnerable D. Endangered Rare

Vulnerable

43. Which among the following statements is incorrect?

A.



B.

41. Some species are found exclusively in a particular area and do not occur naturally anywhere else. Asiatic lion is one such example and is found in ________.



C.



D.



44. Which among the following graph shows level of dissolved oxygen (X ) and bacterial population (Y ) in river, polluted by run off from industries and crop fields.

A. B. C. D.

Rare Critically endangered

Gir forest Jim Corbett National Park Pachmarhi Wildlife Sanctuary Nilgiri Biosphere Reserve

In earthworms, each organism carries both male and female gonads. The penis of male transfers the sperm into the vagina of female. Hormone of adrenal gland controls the metamorphosis in frogs. In Amoeba, only one parent produces new cells.

42. Observe the given flowchart carefully regarding the formation of offspring.

A.



C.



B.



D.





Select the option which correctly identifies the chromosomal composition of (i), (ii), (iii) or (iv)



A. B. C. D.

(i) - 44 + XX (iii) - 44 + XY, (iv) - 46 + XX (ii) - 44 + XY, (iii) - 44 + XY, (iv) - 44 + XX (i) - 46 + XX, (ii) - 46 + XY, (iv) - 44 + XX (i) - 23 + XX, (ii) - 23 + XY, (iii) - 23 + XY

45. Which of the following causes marble cancer?

A.



B.



C.



D.

Depletion of ozone layer by chlorofluorocarbons resulting in increasing amount of UV rays reaching the earth. Increased concentration of CO 2 in atmosphere resulting in global warming. Acid rain containing nitric acid formed by reaction of nitrogen dioxide with water vapour. All of these.

Achievers section Direction (46 to 47) : Read the following passage and answer the questions. Sound can be reflected or absorbed. Surface reflect sound, whether they are far or near. Sometimes sound are absorbed. Soft surface are better absorbers of sound whereas hard surface are better reflectors of sound. The sound heard after reflection from a rigid obstacle i.e., cliff, hillside, wall of a building etc. is called Echo.

6

46. What should be the minimum distance between the source of sound and reflecting body for formation of Echo.

A. C.

9 m 25 m

B. D.

17 m 31 m

47. An Echo is heard after 0.4s, when a person fires a cracker 192.8 m away from a high building. What is speed of sound

Class-8 | Level 2



A. C.

96.4 m s–1 964 m s–1

B. D.

48.2 m s–1 482 m s–1

48. Reema observed that reactions take place in all the given beakers.



B. C.



D.

Autotrophic should be replaced by mixotrophic. Cilia should not be replaced as it is correctly mentioned. Contractile vacuole should be replaced by an oral groove.

50. Refer to the given figure showing human endocrine system and select an incorrect statement regarding it. d e

What could we conclude?

A.



B. C.



D.

49. Read the given paragraph in which few wors have been italicised. Select the incorrect option regarding them.



Euglena is a slipper-shaped, unicellular protozoan commonly found in water. It is a autotrophic animal. Its cell membrane is covered all over by hair like cilia, which help animal to swim. There is a contractile vacuole into which food and water are directed by cilia. A.

f

Q is more reactive than R but less reactive than P. R is less reactive than Q but more reactive than P. R and Q both are more reactive than P but Q is less reactive than R. P is more reactive than Q but less reaction than R.

Euglena should be replaced by Paramecium.

Class-8 | Level 2

g h i



A. B.



C.



D.

Endocrine gland 'd ' controls secretion of gland 'i'. Hormone secreted by 'h' controls sexual characters in females. Glands 'f ' and 'g' together comprise master endocrine gland and their hormones control growth and behaviour. Hormone secreted by 'e' controls body metabolism.

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