Frequency is defined as the number of waves passing a fixed point per unit time.

Frequency is defined as the number of waves passing a fixed point per unit time.

• A. The number of waves per unit time
• B. Energy per cycle
• C. Distance between crests
• D. Speed of the wave

Answer: (A)

Frequency tells you how often waves pass a fixed point in a given time. It counts the number of crests (or cycles) that cross that point per second, so describing it as the number of waves per unit time is the exact definition. The unit is hertz (Hz), or cycles per second, and frequency is independent of how tall the wave is (amplitude). The distance between crests is the wavelength, not frequency, and energy per cycle relates to how much energy a single cycle carries, not how often cycles occur. The speed of the wave is a separate quantity that connects to frequency and wavelength via v = fλ, but it is not the definition of frequency. For example, if six crests pass a point in two seconds, the frequency is 3 Hz.

Frequency tells you how often waves pass a fixed point in a given time. It counts the number of crests (or cycles) that cross that point per second, so describing it as the number of waves per unit time is the exact definition. The unit is hertz (Hz), or cycles per second, and frequency is independent of how tall the wave is (amplitude). The distance between crests is the wavelength, not frequency, and energy per cycle relates to how much energy a single cycle carries, not how often cycles occur. The speed of the wave is a separate quantity that connects to frequency and wavelength via v = fλ, but it is not the definition of frequency. For example, if six crests pass a point in two seconds, the frequency is 3 Hz.