Homework Help: Electric Circuits EMF

1. Oct 30, 2007

Sarliz

1. The problem statement, all variables and given/known data

You'll have to forgive me... I've got some rather poor Physics books with which to consult, so this may seem rather simple. I think I understand the concepts but I don't think I have all of the information from my sources to answer this problem.

A 1.5 V battery stores 4.3 kJ of energy. How long can it light a flashlight bulb that draws 0.6A?

Units should be in hours, but I'm not sure what to do with only having equations V = IR and I = E/R (where E is epsilon, of course). I don't know what part of this factors into time!!!

2. Oct 30, 2007

Kurdt

Staff Emeritus
The electric power in a DC circuit is $P =IV$. Is that enough to get you going?

3. Oct 30, 2007

Sarliz

Guess it'll have to be. Thanks.

4. Oct 30, 2007

Kurdt

Staff Emeritus
If you have more questions I'll be happy to clarify

The units of power are of course Joules/second. That is where the time comes into it.