Question

In a circuit shown in figure, the heat produced in $3$ ohm resistor due to a current flowing in it is $12J$. The heat produced in $4$ ohm resistor is

• A. $2J$
• B. $4J$
• C. $64J$
• D. $32J$

Answer 1

The correct option is B $4J$

For $3\Omega$ resistance heat $=\frac{V^2}{R}=12J$

$V^2=12\times R=36$

$V=\sqrt{36}$

For upper branch in parallel combination

$R_{net}=6\Omega ,V=6V$

$i=\frac{V}{R}=\frac{6}{6}=1A$

Heat produced in $4\Omega$

$P=H=L^{2}R=1^2\left(4\right)=4J$

Hence, the correct option is $\left(B\right)$