Question

How do noise canceling headphones work?

A.) by stopping sound waves

B.) by interfering with sound waves

C.) by using antennas

D.) by transmitting light waves

Answer 1

The answer to the question is B.) by interfering with soundwaves

Your welcome :)

Answer 2

B.) by interfering with sound waves

Step-by-step explanation:

As we know that the interference of sound waves is of two types

1). constructive interference

2). destructive interference

now we know that constructive interference means the resultant intensity will be more than the intensity of interfering waves as here two waves are in same phase.

In destructive interference the resultant of two waves is given by the minimum resultant of the intensity as here the phase of two waves are opposite to each other.

So we will say that

`I = \sqrt{(I_1 + I_2 + 2√(I_1I_2)cos\theta)}`

here in case of noise cancelling headphones we know that the phase of noise is always made in opposite phase with the sound which is used to cancelled the noise.

This will reduce the noise and we will get a clear sound