Question

The amplitude of a sound wave is increased from 1 mm to 2 mm. The loudness of the sound will:

Options

• increase two times

• increase four times

• same

• decrease

Answer 1

Increase four times

Explanation:

Sound intensity is proportional to the square of the amplitude:

I ∝ A²

Doubling the amplitude makes the intensity four times as great, so the loudness increases four times.