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Two electric bulbs have tungsten filamen...

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 lengths are different

Text Solution

Verified by Experts

The correct Answer is:
A

`P = V^(2)//R` . If `P` is more , `R` is less . `R = rho l // a`. For less `R`, a is more . So the `100 W` bulb has thicker element .
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