MCQ
When a potential difference is applied across, the current passing through
- AAn insulator at $0K$ is zero
- BA semiconductor at $0K$ is zero
- CA P-N diode at $300K$ is finite, if it is reverse biased
- ✓All of the above
✓
Answer
Correct option: D.
All of the above
d
(d) At $0 K$, a semiconductor becomes a perfect insulator. Therefore at $0 K$, if some potential difference is applied across an insulator or a semiconductor, current is zero. But a conductor will become a superconductor at $0 K$. Therefore, current will be infinite. In reverse biasing at $300\, K$ through a $P-N$ junction diode, a small finite current flows due to minority charge carriers.
(d) At $0 K$, a semiconductor becomes a perfect insulator. Therefore at $0 K$, if some potential difference is applied across an insulator or a semiconductor, current is zero. But a conductor will become a superconductor at $0 K$. Therefore, current will be infinite. In reverse biasing at $300\, K$ through a $P-N$ junction diode, a small finite current flows due to minority charge carriers.
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