How Much Energy Does Leaving Car Headlights On Drain from a 12V Battery?

AI Thread Summary
Leaving car headlights on for one hour at a current drain of 5A from a 12V battery will significantly deplete the battery's energy. The discussion revolves around calculating the total energy used, which involves understanding Ohm's Law and the relationship between power, current, and voltage. There is uncertainty about whether to consider the battery as ideal or with internal resistance, impacting the calculations. Clarification is sought on how to incorporate time into the energy calculation and the definitions of electrical power and energy. Understanding these concepts is crucial for accurately determining the battery's energy consumption in this scenario.
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Homework Statement



If you accidentaly leave your car headlights (current drain 5A) on for one hour, how much of the 12-V battery's chemical energy is used up?


Homework Equations



Well, there's Ohm's Law...and it's million forms

The Attempt at a Solution



First things first, I'm not sure whether to think of the power source as an ideal battery or not (ie, should I think about an internal resistance or not.)

Ok, the time factor is throwing me off. I'm not sure how to use the time (one hour) in any form of Ohms law. And I'm not sure if the current drain is the current through the battery of the entire circuit or the headlights or what. Any ideas?
 
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