Question

A resistance coil is made by joining in parallel two resistances each of 10$\Omega$. An emf of 1V is applied between the two ends of coil for 5 minutes. Calculate the heat produced in calories.

Answer 1

$R_1=R_2=10\Omega$

$\therefore R_{net}=\frac{R_1{R}_2}{R_1+R_2}=\frac{100}{20}=5\Omega$

$V=1v$

$\therefore P=\frac{V^2}{R}=\frac{1}{5}\Omega =0.2\Omega$

$\therefore$ Heat produced $=0.2=0.05$ calories per second.

$\therefore$ Heat produced for $5min=0.05\times 5\times 60cals$

$=15cal$