Question

A transverse wave on a string has an amplitude A. A tiny spot on the string is colored red. As one cycle of the wave passes by, what is the total distance traveled by the red spot?
a.) 4A
b.) 1/2 A
c.) 1/4 A
d.) A
e.) 2A

Answer 1

Answer: E. 2A

Explanation:

Amplitude(A) of a wave is the displacement of a body from its position of rest. The maximum value of the amplitude is the crest and the minimum value is the trough.

For a wave to make a cycle, it has to move to and from from its point of displacement.

If the red spot on the string completes a cycle, this means it must have pass through the crest and the trough making it 2 amplitudes.