Question

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

• A. $64W$
• B. $31W$
• C. $29W$
• D. $25W$

Answer 1

The correct option is A $64W$

Given$:-$

For bulb$,$

Power , $P=100W,V=200V$

As we know $,$

$P=V^2/R,$

$R=V^2/P$

$=200\times 200/100$

$=400Ohm$

So$,$ For $160V$ supply $,$

as $V=IR$

So$,I=160400=0.4A$

Power Consumption$,$

$P=VI$

$=160\times 0.4$

$=64W$

Hence,

option $\left(A\right)$ is correct answer.