If an alternating voltage is applied across a p-n junction diode in series with a load then

An alternating voltage applied across a p-n junction diode in series with a load produces rectification due to the diode's unidirectional conduction properties.

During the positive half-cycle, the diode is forward biased, allowing current to flow through the load and producing a voltage output. During the negative half-cycle, the diode is reverse biased, blocking current flow and resulting in zero voltage output.

The resulting waveform consists of positive half-cycles only, forming a pulsating DC voltage across the load.