Which statement about frequency units is true?

Which statement about frequency units is true?

• A. Frequency is measured in Hertz, representing cycles per second.
• B. Frequency is measured in Watts.
• C. Frequency is measured in meters.
• D. Frequency is measured in decibels.

Answer: (A)

Frequency is about how many times something repeats each second, so the natural unit is the Hertz, defined as one cycle per second. This directly captures the rate of repetition in time, which is exactly what frequency measures. In radio and signal work you’ll often see frequencies expressed as Hz and scaled to kHz, MHz, or GHz, reflecting how often the repetition occurs in those time units. Other quantities that might come up—Watts, which measures power; meters, which measure length (and relate to wavelength but are not a unit of frequency); and decibels, which express level or ratio on a logarithmic scale—do not measure how often something repeats per second. If you see angular frequency, that’s in radians per second and relates to ordinary frequency by ω = 2πf, but the unit for frequency itself remains Hertz.

Frequency is about how many times something repeats each second, so the natural unit is the Hertz, defined as one cycle per second. This directly captures the rate of repetition in time, which is exactly what frequency measures. In radio and signal work you’ll often see frequencies expressed as Hz and scaled to kHz, MHz, or GHz, reflecting how often the repetition occurs in those time units.

Other quantities that might come up—Watts, which measures power; meters, which measure length (and relate to wavelength but are not a unit of frequency); and decibels, which express level or ratio on a logarithmic scale—do not measure how often something repeats per second. If you see angular frequency, that’s in radians per second and relates to ordinary frequency by ω = 2πf, but the unit for frequency itself remains Hertz.