Which of the following is not a correct state | vedclass

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(D) The power rating of a bulb is given by $P = V^2 / R$. For a constant voltage $V$,the resistance $R = V^2 / P$. Since $P_{40} = 40 \ W$ and $P_{60}

Vedclass · Accepted Answer

Resistance of a $40 \ W$ bulb is less than the resistance of a $60 \ W$ bulb.

Vedclass · Answer

(D) The power rating of a bulb is given by $P = V^2 / R$. For a constant voltage $V$,the resistance $R = V^2 / P$. Since $P_{40} = 40 \ W$ and $P_{60} = 60 \ W$,we have $R_{40} = V^2 / 40$ and $R_{60} = V^2 / 60$. Clearly,$R_{40} > R_{60}$,so option $D$ is incorrect. In series,the current $I$ is the same,and power dissipated is $P' = I^2 R$. Since $R_{40} > R_{60}$,the $40 \ W$ bulb dissipates more power and glows brighter. Thus,the statement in option $D$ is false.

Which of the following is not a correct statement?

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