posted by natali on .
A 100W light bulb is left on for 10hrs. Over this period of time how much energy is used by the bulb?
am i doing this right?
my guess is to convert 100W to kW
and convert 10 hrs to seconds and multiply the 2 together?
which gives 3600J or should i just leave it in watts?
Energy is in joules. Power is in watts.
Sometimes electrical energy is spoken of as watt-hours, or watt-seconds, or kw-hrs. But in the end, joules is energy.
Multiply watts x time to get energy.