An electric appliance has a resistance of and is designed to operate at

PHYSICS · Single correct · A Level · Physics · Electricity · Electricity

Problem

An electric appliance has a resistance of

30\,\Omega

and is designed to operate at

120\,\text{V}

. It is to be connected to a

240\,\text{V}

mains supply. What resistance should be connected in series with the appliance so that it continues to draw its rated current? (a)

60\,\Omega

(b)

90\,\Omega

(c)

30\,\Omega

(d)

15\,\Omega