A good diode checked by a multimeter should indicate:
Show Hint
- high resistance in reverse bias and a low resistance in forward bias
- high resistance in both forward bias and reverse bias
- low resistance in both reverse bias and forward bias
- high resistance in forward bias and low resistance in reverse bias
The Correct Option is A
Solution and Explanation
Forward bias → conducts easily (low resistance)
Reverse bias → blocks current (high resistance)
This property is used to test diodes using a multimeter.
Step 1: Forward bias behaviour. When the diode is forward biased:
Depletion region narrows
Current flows easily
Multimeter shows low resistance
Step 2: Reverse bias behaviour. When reverse biased:
Depletion region widens
Very small leakage current
Multimeter shows high resistance
Step 3: Conclusion. A good diode must:
Conduct in forward bias (low resistance)
Block in reverse bias (high resistance)
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