MATHEMATICS · Multi-part · ISC · Physics · Current Electricity · Electrical energy and power
Problem
Two filament lamps are each rated 40 W – 120 V. They are available in a laboratory where the mains voltage is 240 V.
(a) Show with calculations whether the lamps should be connected in series or in parallel to operate at normal brightness from the 240 V supply.
(b) For the arrangement chosen in part (a), determine the current drawn from the mains and the total power consumed by the two lamps.