MCQ
A $5\,^oC$ rise in temperature is observed in a conductor by passing a current. When the current is doubled the rise in temperature will be approximately ........... $^oC$
- A$16$
- B$10$
- ✓$20$
- D$12$
✓
Answer
Correct option: C.
$20$
c
Since $H \propto {i^2},$ so on doubling the current, the heat produced and hence the rise in temperature becomes four times.
Since $H \propto {i^2},$ so on doubling the current, the heat produced and hence the rise in temperature becomes four times.
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