set 11 MCQ Questions & Answers Detailed Explanation

Question : 1

‘Pitch’ is a characteristic of sound that depends upon its

a) fequency

b) intensity

c) quality

d) None of these

Question : 2

A ray of light travels from medium I to medium II. The figure given shows the variation of sin of angles of incidence (sin i) in medium I with sin of angle of refraction (sin r) in medium II.

1. Speed of light in medium I > Speed of light in medium II.
2. Speed of light in medium I < Speed of light in medium II.
3. Light travels from denser medium to rarer medium.

a) 1 and 3

b) 1 only

c) 2 only

d) 2 and 3

Question : 3

A glass bottle containing water tightly corked breaks when it is kep in freeze, because

a) The volume of water decreases on freezing

b) The volume of water increases on freezing

c) Bottle shrinks on freezing

d) Glass is the bad conductor of heat

Question : 4

Assertion (A):
In the visible spectrum of light, red light is more energetic than green light.
Reason (R):
The wavelength of red light is more than that of green light.
Code

a) (A) is true, but (R) is false

b) Both (A) and (R) are true, but (R) is not the correct explanation of (A)

c) Both (A) and (R) are true and (R) is the correct explanation of (A)

d) (A) is false, but (R) is true

Question : 5

The gas used in discharge tubes for optical decoration and advertising is

a) Sulphur dioxide

b) Ammonia

c) Carbon dioxide

d) Neon

Question : 6

For shaving, one uses

a) Convex mirror

b) Plain mirror

c) Concave mirror

d) None of the above