If two electric bulbs have 40, W and 60, W ra | vedclass

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(D) The power rating of an electric bulb is given by the formula $P = \frac{V^2}{R}$,where $V$ is the voltage and $R$ is the resistance.Since both bul

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$3:2$

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(D) The power rating of an electric bulb is given by the formula $P = \frac{V^2}{R}$,where $V$ is the voltage and $R$ is the resistance.Since both bulbs are rated at the same voltage $V = 220\, V$,the resistance $R$ is inversely proportional to the power $P$,i.e.,$R \propto \frac{1}{P}$.Therefore,the ratio of their resistances is given by $\frac{R_1}{R_2} = \frac{P_2}{P_1}$.Given $P_1 = 40\, W$ and $P_2 = 60\, W$,we have $\frac{R_1}{R_2} = \frac{60}{40} = \frac{3}{2}$.Thus,the ratio of their resistances is $3:2$.

If two electric bulbs have $40\, W$ and $60\, W$ rating at $220\, V$,then the ratio of their resistances will be

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