Question

What will be the resistance of a lamp, rated for 220V-500W and connected across a 110 volt supply?

Answer 1

Explanation:

$P = 500 \: Watt$

$V = 220 \: volt$

$As \: we \: know-$

$\huge\boxed{P = VI}$

$500 = 220 * I$

$I =\frac{500}{220}$

$I =\frac{25}{11} A$

$Now ,$

$When , V = 110 \: volt$

$R =\frac{V}{I}$

$R =\frac{110}{\frac{25}{11}}$

$R =\frac{1210}{25}$

$R =\frac{4840}{100}$

$R = 48.4 \: ohm$