AFOQT Practice Test

What is the definition of amplitude in wave terms?

1. Distance between the crest and trough

2. Distance between the midline and the crest (or trough)

3. Distance between two consecutive waves

4. Time taken for a wave cycle to occur

The correct answer is: Distance between the midline and the crest (or trough)

Amplitude is defined as the maximum distance that a point on a wave moves from its rest position or midline, which is specifically measured to either the crest (the peak of the wave) or the trough (the lowest point of the wave). Therefore, the distance from the midline to the crest (or trough) accurately captures this concept of amplitude; it represents the extent of motion that the wave undergoes from its equilibrium position. For context, the other options describe different characteristics of wave behavior. The distance between the crest and trough gives a measurement related to the wave height but does not define amplitude specifically. The distance between two consecutive waves relates to the wavelength, while the time taken for a wave cycle to occur refers to the wave period, none of which align with the fundamental definition of amplitude.