Alternating Current
Direct Current or DC is electricity that has a constant voltage. It is the type of electricity required for most electronic devices. However, the electricity that is easiest to generate is Alternating Current or AC.
Alternating current is one whose voltage changes with time. If you look at the graph it looks like sine wave. The voltage also switches direction as it goes from positive to negative. This means that the electrons are also changing their direction. You can imagine AC current as someone switching the electrodes around on a power supply so that the negative electrode becomes positive and the positive negative, and then switching it back.
Alternating current is one whose voltage changes with time. If you look at the graph it looks like sine wave. The voltage also switches direction as it goes from positive to negative. This means that the electrons are also changing their direction. You can imagine AC current as someone switching the electrodes around on a power supply so that the negative electrode becomes positive and the positive negative, and then switching it back.
DC current is shown as a straight line because the voltage is constant but AC is the red wave.
AC current is described in the same way as all other waves. It is usually described with a peak voltage and a frequency, which is how many times it completes a full cycle every second. Mains electricity has a peak voltage of 240V and a frequency of 50Hz. Have a look at the simulator below to see the movement of current in AC electricity. |