AC current

Definition

AC current (Alternating Current) is an electric current that reverses its direction periodically. It is the form of electrical energy commonly delivered to businesses and residences.

5 Must Know Facts For Your Next Test

1. The frequency of AC current in the United States is 60 Hz, while in many other countries it is 50 Hz.
2. AC current can be easily transformed to different voltages using transformers.
3. It is represented mathematically as $I(t) = I_0 \sin(2 \pi f t)$, where $I_0$ is the maximum current, $f$ is the frequency, and $t$ is time.
4. AC current is used in most household appliances due to its efficiency in long-distance transmission.
5. Nikola Tesla and George Westinghouse were pioneers in promoting AC over DC for commercial power distribution.

Review Questions

• What are the main differences between AC and DC currents?
• How does the frequency of AC current differ between countries like the United States and Europe?
• Why can AC current be easily transformed to different voltages?

Related terms

Direct Current (DC): An electric current that flows in one direction only.

Transformer:

A device used to change the voltage of an alternating current.

Frequency:

The number of cycles per second in an alternating current, measured in Hertz (Hz).