Question.
An electric iron of resistance $20 \Omega$ takes a current of 5 A. Calculate the heat developed in $30 \mathrm{~s} .$
An electric iron of resistance $20 \Omega$ takes a current of 5 A. Calculate the heat developed in $30 \mathrm{~s} .$
solution:
Here, resistance, $R=20 \Omega$, current, $I=5 A$, time, $t=30 \mathrm{~s}$.
Heat produced, $\mathrm{H}=\mathrm{I}^{2} \mathrm{R} \mathrm{t}=(5)^{2} \times 20 \times 30$
$=1.5 \times 10^{4} \mathrm{~J}$
Here, resistance, $R=20 \Omega$, current, $I=5 A$, time, $t=30 \mathrm{~s}$.
Heat produced, $\mathrm{H}=\mathrm{I}^{2} \mathrm{R} \mathrm{t}=(5)^{2} \times 20 \times 30$
$=1.5 \times 10^{4} \mathrm{~J}$