Gate triggering of a reverse-biased thyristor A thyristor (SCR) is reverse biased between anode and cathode. If a positive gate pulse is applied, what happens?

Introduction / Context:Thyristors require two conditions to conduct: proper gate triggering and correct anode-to-cathode polarity (forward bias). Gate pulses alone cannot force conduction against a reverse anode-cathode voltage.

Given Data / Assumptions:

• Anode is at a lower potential than cathode (reverse bias).
• Gate receives a positive pulse referenced to cathode.

Concept / Approach:Gate triggering lowers the forward breakover requirement when the device is forward-biased. Under reverse bias, the junctions are not in a state that supports thyristor conduction; the device remains off, aside from small leakage current, until forward bias is restored.

Step-by-Step Solution:Identify device state: reverse biased anode-cathode.Apply gate pulse: does not overcome reverse blocking capability.Conclusion: device stays off.

Verification / Alternative check:Device I-V curves show negligible gate influence in reverse quadrant; turn-on requires forward quadrant conditions.

Why Other Options Are Wrong:Will turn on (A) / after delay (D): Not possible under reverse bias.May or may not (B): Ambiguous; physics says it will not under reverse bias.

Common Pitfalls:Assuming the gate alone can force conduction in any polarity; SCRs are polarity-sensitive controlled devices.

Final Answer:It will not turn on