Frequency is measured in __________.

• A. hertz
• B. volts
• C. amps
• D. ohms

Answer: (A)

Frequency tells you how many times something repeats each second. The standard unit for that rate is the Hertz (Hz). This unit is used for all repeating signals, from audio waves to radio signals and electrical mains. The other terms measure different electrical properties: volts measure electrical potential, amps measure current, and ohms measure resistance. For example, household power in the United States runs at about 60 Hz, while many other places use 50 Hz. The frequency is the reciprocal of the period: f = 1/T, so a shorter cycle time means a higher frequency.