If the amplitude of a wave is doubled, how does this affect the intensity?

When the amplitude of a wave is doubled, the intensity of the wave increases by the square of the amplitude. Intensity is proportional to the square of the amplitude, which means that if the amplitude is increased by a factor, the intensity will be increased by that factor squared.

In this case, if the amplitude is doubled (increased by a factor of 2), the intensity becomes 2^2, or 4 times greater than the original intensity. This relationship is fundamental in wave physics and can be observed in various types of waves, including sound and electromagnetic waves.

Thus, the correct conclusion is that when the amplitude of a wave is doubled, the intensity indeed becomes quadrapled.