Nate Electrical Practice Exam

What type of rectification does a bridge circuit provide when four diodes are used?

1. Half wave rectification

2. Full wave rectification

3. Pulsating AC

4. None of the above

The correct answer is: Full wave rectification

A bridge circuit using four diodes is designed to provide full wave rectification. In this setup, the arrangement allows for both halves of the AC input signal to be utilized, effectively converting it into a unidirectional current. During the positive half-cycle of the AC waveform, two of the diodes conduct, allowing current to flow through the load in one direction. When the AC waveform transitions to the negative half-cycle, the other two diodes become active, still allowing current to flow through the load in the same direction as during the positive cycle. This action results in a continuous output waveform that consists of both halves of the AC signal, giving it a smoother and more consistent DC output compared to half-wave rectification. In contrast, half-wave rectification only utilizes one half of the AC cycle, leading to a pulsating DC output with significant gaps during the non-conducting half of the AC cycle. While pulsating AC refers to the original alternating current waveform before any rectification process is applied, it does not represent rectified output. The choice of 'none of the above' is not applicable because full wave rectification is indeed achieved through the bridge circuit with four diodes.