Current Electricity 5 Question 13
13. When a potential difference is applied across, the current passing through
(a) an insulator at $0 K$ is zero
(1999, 3M)
(b) a semiconductor at $0 K$ is zero
(c) a metal at $0 K$ is finite
(d) a $p$ - $n$ diode at $300 K$ is finite, if it is reverse biased
Value Based Type Question
Show Answer
Solution:
- At $0 K$, a semiconductor becomes a perfect insulator. Therefore, at $0 K$, if some potential difference is applied across an insulator or semiconductor, current is zero. But a conductor will become a super conductors 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.
