set 6 MCQ Questions & Answers Detailed Explanation

Question : 1

How much should minimum distance be between the source of sound and reflecting surface, so that an echo can be heard clearly?

a) 17 metre

b) 24 metre

c) 10 metre

d) 30 metre

Question : 2

A shrill sound has a ______ pitch and a dull sound has a _____ pitch.

a) low, low

b) high, low

c) low, high

d) high, high

Question : 3

The principle reason why it is better to have two eyes than one is that

a) It gives a man a type of vision known as mosaic vision

b) By having two eyes we can easily see in the dark as well in dim light

c) By having two eyes we can distinguish colour easily

d) It enhances distance and depth perception in us

Question : 4

Which of the following statements is correct ?

a) Frequency of ultrasonic waves is of the same order as that of X-rays

b) Ultrasonic waves can travel in vacuum

c) Wavelength of ultrasonic waves is of the same order as that of microwaves

d) Speed of ultrasonic waves is of the same order as that of light

Question : 5

Optical fibre works on the principle of

a) Scattering

b) Refraction

c) Total internal reflection

d) Interference

Question : 6

Some common mediums in which the speed of sound waves is measured are mentioned below?

1. Air
2. Steel
3. Copper
4. Water

a) 1 < 4 < 3 < 2

b) 1 < 4 < 2 < 3

c) 4 < 1 < 2 < 3

d) 4 < 1 < 3 < 2