Question

A full-wave rectifer with diodes D₁ and D₂ is used to rectify 50 Hz alternating voltage. The diode D₁ conducts _______ times in one second.

• A. 25
• B. 75
• C. 50
• D. 100

Answer 1

The Correct Option is C

In a full-wave rectifier, both diodes conduct during both the positive and negative cycles of the input AC signal. For a 50 Hz AC input, the signal oscillates 50 times per second. Since the full-wave rectifier uses both halves of the AC cycle, diode D1 will conduct during both the positive and negative halves. This results in D1 conducting twice during each cycle, which equals 50 cycles per second. Therefore, diode D1 conducts 50 times in one second. 

Answer 2

1. Understand the Input Signal: The input is an alternating voltage with a frequency of 50 Hz. This means the voltage completes 50 full cycles in one second. Each cycle consists of a positive half-cycle and a negative half-cycle.

2. Understand Full-Wave Rectification (with 2 diodes): In a typical center-tapped full-wave rectifier using two diodes (D₁ and D₂):

• Diode D₁ conducts during one half-cycle of the input AC voltage (e.g., the positive half-cycle).
• Diode D₂ conducts during the other half-cycle of the input AC voltage (e.g., the negative half-cycle).

This arrangement ensures that current flows through the load during both half-cycles of the input AC.

3. Determine Conduction Frequency for Diode D₁:

• Since diode D₁ conducts only during one specific half-cycle (either positive or negative, depending on the setup), it conducts exactly once for every full cycle of the input AC voltage.
• The input frequency is 50 Hz, meaning there are 50 full cycles per second.
• Therefore, diode D₁ conducts once per cycle, resulting in 50 conductions in one second.

4. Conclusion: Diode D₁ conducts 50 times in one second.

Answer: The correct option is (C) 50.