A 500W 220V bulb is supplied with 110V power consumption by the bulb will be

Text Solution

Solution : Power of the bulb, `P=100W` <br> Operating voltage `V=200V` <br> Resistance of the bulb,`R=(V^(2))/(P)=((220)^(2))/(100)=484Omega` <br> Actual operating voltage `V^(1)=110V` <br> Therefore, power consumed by the bulb, <br> `P^(1)((V^(1))^(2))/(R)=((110)^(2))/(484)=25W`

A 500 W, 220 V bulb is supplied with 110V.

Power consumption by the bulb will be

A. slightly less than 125 W B. slightly greater than 125 W C. exactly 125 W

D. 250 W

Answer: B

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An electric bulb is rated 220 V and 100 W. When it is operated on 110 V, what will be the power consumed?

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