COMEDK · Physics · 19. Current Electricity
The resistance of mercury at \(4.2 \mathrm{~K}\) is
- A infinity
- B greater than at lab temperature
- C same as that of lab temperature
- D almost zero
Answer & Solution
Correct Answer
(D) almost zero
Step-by-step Solution
Detailed explanation
At \(4.2 \mathrm{~K}\), the resistance of mercury suddenly drops to zero and behaves as a super conductor at this temperature (called critical temperature).
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