CBSE Class 8 Science Sample Paper Set 25

CBSE Class 8 Science Sample Paper Set Y. Revision worksheets, Sample papers, Question banks and easy to learn study notes for all classes and subjects based on CBSE and NCERT guidelines. Students and parents can download free a collection of all study material issued by various best schools in India. The study material has been carefully compiled by the best teachers in India. The students should practice the questions database to get better marks in examination. Please refer to other links for free download of high quality study material. Based on CBSE and NCERT  guidelines. Based on the same pattern as released by CBSE every year. Study material for final/ term/ SA1/ SA2 Examinations conducted by various schools affiliated to Central Board of Secondary Education (CBSE) in India and abroad. CBSE Study material has been compiled to help students preparation which will helps the students to concentrate more in areas which carry more marks.

SECTION- A

1. Potable water should be

a. Colourless b. odourless c. tasteless d.all the above

2. Select the correct statement.

a. Speed of violet colour is maximum and red colour is minimum.

b. Violet colour bends the least during dispersion

c. speed of red colour is maximum and violet colour is minimum.

d. Dispersion of white light can be seen when it passes through a rarer medium.

3. The fibre which resembles wool

a. Terylene b. Rayon c. Acrylon d.Nylon

4. Which of the following facts are true for sound?

i. Sound needs a medium for its propagation

ii. Sound propagates fastest in gases.

iii. Speed of sound is faster than speed of light.

iv. sounds with frequencies below 20Hz are called infrasonic sounds.

a. Only i b. both i&ii c. both iii&iv d. both i&iv

5. What is the principle behind the treatment of industrial waste?

6. _________________ controls the amount of light entering the eye so that the image can be formed on the .

7. Why is blind spot of the eye called so?

8.How is calorific value of fuel related to its efficiency?

9. It is not advisable to wear synthetic clothes in science laboratory. Why?

10. What are asteroids?

11. How do agricultural activities contribute to water pollution?

12. Identify the eye defects in the given cases and suggest suitable remedies for the same.

a. Image formed behind the retina .

b. a thin membrane develops over the lens.

13. Can water become fit for drinking by adding alum or filtering? Justify.

14. The speed of light in a given medium is taken as an indicator of its optical density. Explain.

15. Explain the reason behind the formation of Echo.

16. What would happen if

a. we keep a glass tube in the innermost Zone of the flame?

b. unburnt carbon particles are released in air?

17. a. Differentiate between tactual aids and auditory aids. Give one example for each.
b. Give one application of persistence of vision.

a. Where was the object kept?

b. Suppose the object is kept at 24 cm from the lens. Where would you get the image?

c. Represent the Principal focus of concave lens with a ray diagram.

19. Predict the consequences in the following situations.

a. Auditory nerve gets damaged

b. Persistence of hearing does not exist.

c. continuous exposure to loudspeakers.

20.Two substances A and B are kept in open air. Substance A caught fire. When substance B was supplied with a small amount of heat, it burnt uncontrollably releasing large amount of heat.

a. Name the two substances and the type of combustion exhibited by them.

b. Give the reason behind the difference in behaviour of these two substances.

21. Design an activity to compare the tensile strength of cotton and nylon fibres.

22.Explain the reason behind the following facts:
i.formation of colourful bands in Jupiter.
ii.Comets develop a tail only when they come near the sun.
iii.Geostationary satellites are a boon in the field of communication

25. a. Mention 2 measures to limit noise pollution .
      b. People living near railway tracks know well in advance about an approaching train. Give reason.
      c. How does mechanism of production of sound in birds differ from that of human beings?
OR
a. Describe a simple experiment to show sound cannot propagate through vacuum.
b. What is the effect on thei.
i loudness of a sound when the amplitude of the vibrating body gets doubled?
ii. pitch of a sound when the frequency of the vibrating body gets doubled?

26. a. CNG can be considered a good fuel compared to coal. Justify with two points.
      b. Give reasons:
         i.Dry leaves catch fire easily than wet ones.
        ii. Sand can be used as a fire extinguisher
       iii.Incomplete combustion of fuels can cause health hazards.
OR
a.Write an activity to prove that Non-luminous Zone of flame is hottest Zone.
b. LPG, Coal, Diesel, wood, petrol
   i) In the above list of fuels, one of them has the lowest ignition temperature. This fuel can be preferred over other fuels due to some of its advantages. Can you suggest two advantages of this fuel?
   ii) How does burning of some of these fuels lead to acid rain?
c. Why is water not used in controlling electric fires?

Please refer to attached file for CBSE Class 8 Science Sample Paper Set Y.