Question

When the current in a conductor is doubled, keeping other parameters constant, the heating effect of the current becomes ___ .

• A. is doubled
• B. becomes 4 times
• C. becomes 3 times
• D. is unaffected

Answer 1

The correct option is B

becomes 4 times

If current is doubled, the heating effect of a current through a conductor becomes 4 times of the original.

as, H = $i^2$Rt .
$H_1$ = $i^2$Rt ,
$H_2$ = ${\left(2i\right)}^2$Rt
$H_2$ = 4${\left(i\right)}^2$Rt
= 4$H_1$