Practice Amplitude in Physics
Use these practice problems to test your method after reviewing the concept explanation and worked examples.
Quick Recap
The maximum displacement of a wave from its equilibrium (rest) position, measuring the wave's strength or intensity.
How 'tall' the wave is measured from the center line — bigger amplitude carries more energy and produces stronger effects.
Example 1
easyA speaker produces a sound wave. The air molecules vibrate 0.002 \text{ m} on either side of their equilibrium position. What is the amplitude of the sound wave?
Example 2
mediumTwo identical waves with amplitude A = 3 \text{ cm} overlap perfectly in phase. What is the resulting amplitude? What if they are perfectly out of phase (shifted by half a wavelength)?
Example 3
mediumA wave on a string has amplitude 0.1 \text{ m} and frequency 2 \text{ Hz}. The string has a linear mass density of 0.05 \text{ kg/m} and the wave speed is 10 \text{ m/s}. What is the power transmitted by the wave? Use P = \frac{1}{2}\mu\omega^2 A^2 v.
Example 4
hardA seismograph records an earthquake wave with amplitude 2 \text{ mm}. A second earthquake produces waves with 4 times the energy. What is the amplitude of the second earthquake's waves?