Homework Help: physics

Posted by natali on Monday, October 22, 2007 at 3:14am.

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?

physics - bobpursley, Monday, October 22, 2007 at 8:27am
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.

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