Question

I. For the normal human eye the near point is at ………………. cm.

A. 10

B. 20

C. 25

D. 30


II. A lens does not produce any deviation of a ray of light passing through …………

A. its centre of curvature

B. its optical centre

C. its principal focus

D. none of the above


III. The reaction of iron nail with copper sulphate solution is ………………… reaction.

A. double displacement

B. displacement

C. combination

D. decomposition


IV. The image obtained while finding the focal length of a convex lens is ……………..

A. real and erect

B. virtual and erect

C. real and inverted

D. virtual and inverted


V. Oily food kept out for a few days gives a bad taste and a bad smell because of ……….

A. corrosion

B. displacement

C. heating

D. rancidity​

Answer 1

Explanation:

1. 25 cm

2. its optical centre

3. displacement reaction

4. real and inverted

5. rancidity

hope these answers are correct

Answer 2

Answer:

1) 25cm

2)optical centre

3)displacement

4)rancidity