How does the phase difference between voltage and current vary in an AC circuit?

The phase difference between voltage and current varies in an AC circuit.

In an AC circuit, the voltage and current are constantly changing direction and magnitude. The relationship between the voltage and current is described by their phase difference. The phase difference is the angle between the voltage and current waveforms and is measured in degrees or radians.

When the voltage and current are in phase, they reach their maximum and minimum values at the same time. This means that the voltage and current waveforms are aligned and have a phase difference of 0 degrees. In this case, the power factor is 1, which means that all the power supplied by the source is being used by the load.

When the voltage and current are out of phase, they do not reach their maximum and minimum values at the same time. This means that the voltage and current waveforms are not aligned and have a phase difference of more than 0 degrees. In this case, the power factor is less than 1, which means that some of the power supplied by the source is not being used by the load.

The phase difference between voltage and current can be calculated using trigonometry. The cosine of the phase angle is equal to the power factor. The phase difference can also be measured using an oscilloscope, which displays the voltage and current waveforms on a screen.

In summary, the phase difference between voltage and current varies in an AC circuit depending on whether they are in phase or out of phase. When they are in phase, the power factor is 1, and when they are out of phase, the power factor is less than 1. The phase difference can be calculated using trigonometry or measured using an oscilloscope.