Q20 of 54 Page 389

A source of wave produces, 40 crests and 40 troughs in 0.4 seconds. Find the frequency of the wave.

Given,

There are 40 crests and 40 troughs.

One crest and and one trough constitutes one cycle.

So, total number of cycles = 40

One cycle denotes one time period.

A sound wave of length 70 cm travels 840 m in 25 seconds. What is the velocity and frequency of sound?

An echo is heard after 0.8 seconds, when a person fires a cracker 132.8 m from a high buildings. Calculate the speed of sound.

Why an echo is not heard when distance between source of sound and reflecting body is 10 m?

The distance between the crest and trough of a transverse wave is 15 cm, what is the velocity of the wave if its frequency is 1000 Hz?