A ( 100 W , 200 V ) bulb is connected to a 160 V power supply. The power consumption would be

Question

A ( 100 W , 200 V ) bulb is connected to a 160 V power supply. The power consumption would be (A) 125W (B) 100 W (C) 80W (D) 64W

Tardigrade Admin · Accepted Answer

Power = 100W , Voltage = 200V The resistance of bulb = ( textitV2/ textitP)=(2 0 0 × 2 0 0/1 0 0)=400Ω When the bulb is connected across 160V , Current in bulb = (1 6 0/4 0 0) textA Power consumption = textitVI=160× (1 6 0/4 0 0) =64W

Q. A ( $100 W$ , $200 V$ ) bulb is connected to a $160 V$ power supply. The power consumption would be

$125 W$

$100 W$

$80 W$

$64 W$

Power = $100 W$ , Voltage = $200 V$
The resistance of bulb = $\frac{V ^{2}}{P} = \frac{200 \times 200}{100} = 400Ω$
When the bulb is connected across $160 V$ ,
Current in bulb = $\frac{160}{400} A$
Power consumption = $VI = 160 \times \frac{160}{400}$ $= 64 W$

Q. A ( 100W , 200V ) bulb is connected to a 160V power supply. The power consumption would be

125W

100W

80W

64W