chapter 2 Mcqs - Sound

Question 1

What is not true for sound?

Answer 1

Sound transfers energy along with matter of medium

(sound only transfers energy, not matter)

Question 2

Sound travels faster in

Answer 2

Steel

Question 3

Speed of sound in air at 0 C is 332 ms-1. What is its speed of sound in vacuum?

Answer 3

Zero

(sound does not propagate in air)

Question 4

Threshold of hearing has —- intensity level

Answer 4

0 db

Question 5

If frequency of sound in air is doubled, its speed will —

Answer 5

remain the same

Question 6

Sounds having frequency less than
— are called infrasonic waves

Answer 6

20 hz

Question 7

Minimum distance of a person from obstacle for sound to hear an echo is

Answer 7

17 m

Question 8

Which of the following properties of waves is directly related to the loudness of sound?

Answer 8

Amplitude

Question 9

Intensity of threshold of pain (loudest sound without pain)

Answer 9

1 watt per square meter (Wm-²)

Question 10

Silent whistle is used to train dogs, when the whistle is blown but the trainer does not hear it. its possible that its frequency is

Answer 10

f > 20000 Hz