Two electric bulbs have tungsten filament of same length. If one of them gives $60\ W$ and the other $100\ W$ , then
A$100\ W$ bulb has thicker filament
B$60\ W$ bulb has thicker filament
C
Both filaments are of same thickness
D
It is not possible to get different wattages unless the length are different
Medium
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A$100\ W$ bulb has thicker filament
a $P=V^{2} / R \cdot$ If $\mathrm{P}$ is more, $\mathrm{R}$ is less. $R=\rho \ell / a.$
For less $\mathrm{R},$ $''\mathrm{a}''$ is more. So, the $100 \mathrm{\,W}$ bulb has thicker element.
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