Amplitude is the maximum displacement from equilibrium; wavelength is the distance between successive equivalent points. Frequency is the number of complete oscillations per second in hertz. Period is the time for one complete oscillation: T = 1/f. Distinguish amplitude from crest-to-trough height and wavelength from the length of the entire wave train. Example: A wave has frequency 15 Hz. Calculate its period. T = 1/f = 1/15 = 0.066667 s. Use clear labels. Explain the result. State assumptions.