Question

If the amplitude of a sound wave is tripled,
By what factors will the intensity increase?

Answer 1

We know, $A^2-I$...(i)

Amplitude of sound wave is tripled

New amplitude is 3A and new intensity will be $I_o$

$(3A{)}^2=I_o$

$9(A{)}^2=I_o$

So, from equation (i) ,

$9I=I_o$

Hence, intensity increase by 9 times.