Which uses more current? (2) 30watt lightbulbs vs one 60watt?

Question

Which uses more current? (2) 30watt lightbulbs vs one 60watt?

Answer 1

P - i^2 * R

Answer 2

Both takes same current.You are connecting two lamps in parrelel. So total wattage is 30+30=60watts.

Answer 3

Theoretically the same; however, the individual bulb has a slight inefficiency resulting from the resistance in the base contacts and the internal wiring.

So if it is a trick question, the answer is that the arrangement with two 30 watt bulbs will use a tiny fraction of one percent more current than the one 60 watt bulb.

If it were a practical question in the real world, the other trick is that nobody manufactures a 30 watt incandescent bulb of the household type.  So in a practical experiment you might have to use other sizes or types.