(A) The rate of heat production (power) in a resistor is given by the formula $H = \frac{V^2}{R}$.In the first case, the power is $H = \frac{V^2}{R}$.

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(A) The rate of heat production (power) in a resistor is given by the formula $H = \frac{V^2}{R}$.In the first case, the power is $H = \frac{V^2}{R}$.In the second case, the new voltage is $V' = \frac{V}{3}$ and the new resistance is $R' = 2R$.The new rate of heat production $H'$ is given by:$H' = \frac{(V')^2}{R'} = \frac{(\frac{V}{3})^2}{2R} = \frac{\frac{V^2}{9}}{2R} = \frac{V^2}{18R}$.Since $H = \frac{V^2}{R}$, we can substitute this into the equation:$H' = \frac{H}{18}$.

Class 12 Physics Current Electricity Electrical Energy and Power

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Heat is produced at a rate given by $H$ in a resistor when it is connected across a supply of voltage $V$. If now the resistance of the resistor is doubled and the supply voltage is made $V / 3$, then the rate of production of heat in the resistor will be

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A
$H / 18$
B
$H / 9$
C
$6 H$
D
$18 H$

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Heat is produced at a rate given by $H$ in a resistor when it is connected across a supply of voltage $V$. If now the resistance of the resistor is doubled and the supply voltage is made $V / 3$, then the rate of production of heat in the resistor will be

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$A$ resistor develops $500 \, J$ of thermal energy in $20 \, s$ when a current of $1.5 \, A$ is passed through it. If the current is increased from $1.5 \, A$ to $3 \, A$,what will be the energy (in $J$) developed in $20 \, s$?

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