Question

Two waves carry the same power, but the first wave covers 3 times the area as the second. How do the intensities of the two waves compare?

Answer 1

Intensity of first wave will 1/3 the intensity of second wave.

Step-by-step explanation:

Intensity of the wave is defined as the change in power with the respect to area of the wave.

Mathematically,

`I=(P)/(A)`

According to question, the power of the two waves are same but the area covers by the first wave is equal to 3 times the area cover by the second wave.

Therefore,

`P_(1) =P_(2) \\I_(1)A_(1) = I_(2)A_(2)`

Now according to question,

`I_(1)3A_(2) =I_(2)A_(2)\\I_(1)=(1)/(3)I_(2)`

Therefore, the intensity of first wave will become 1/3 times the intensity of second wave.