Question

If the current is flowing through a 10 $\Omega$ resistor, then indicate in which case the maximum heat will be generated?

• A. Current of $5A$ flows for $2\text{minutes}$
• B. Current of $4A$ flows for $3\text{minutes}$
• C. Current of $3A$ flows for $6\text{minutes}$
• D. Current of $2A$ flows for $5\text{minutes}$

Answer 1

The correct option is C Current of $3A$ flows for $6\text{minutes}$

The heat produced is given by
$H=I^{2}Rt$
(where $H=$ Heat produced, $I=$ current, $R=$ resistance, and $t=$ time)

Option A:

$5A$ flows for $2\text{minutes}$
$H=5^2\times 10\times 2=500J$

Option B:

$4A$ flows for $3\text{minutes}$

$H=4^2\times 10\times 3=480J$

Option C:
$3A$ flows for $6\text{minutes}$
$H=3^2\times 10\times 6=540J$

Option D:
$2A$ flows for $5\text{minutes}$
$H=2^2\times 10\times 5=200J$

Hence, option C is correct.