What is amplitude?

What is amplitude?

• A. The distance between crests
• B. The speed of the wave
• C. The energy of the wave
• D. The measurement from the middle level of a wave to the crest (or to the trough)

Answer: (D)

Amplitude is the maximum distance the particles of a medium move away from their resting position as a wave passes. In a transverse wave, the medium oscillates around the equilibrium line, and the height from this middle line up to a crest (or down to a trough) is the amplitude. The distance between crests is the wavelength, not amplitude, and the speed is how fast the wave moves, determined by the medium and other factors. Energy is related to amplitude (larger amplitude generally means more energy) but is not the same thing as amplitude. So the measure from the middle level to a crest or to a trough is amplitude.

Amplitude is the maximum distance the particles of a medium move away from their resting position as a wave passes. In a transverse wave, the medium oscillates around the equilibrium line, and the height from this middle line up to a crest (or down to a trough) is the amplitude. The distance between crests is the wavelength, not amplitude, and the speed is how fast the wave moves, determined by the medium and other factors. Energy is related to amplitude (larger amplitude generally means more energy) but is not the same thing as amplitude. So the measure from the middle level to a crest or to a trough is amplitude.