Question

A car owner forgets to turn off the headlights of his car while it is parked in his garage. If the 12.0-V battery in his car is rated at 90.0 (A.h) and each headlight requires 36.0 W of power, how long will it take the battery to completely discharge?

Answer 1

It will take the battery 15 hours to discharge completely.

Energy stored in a battery

Energy is defined as the ability or capacity to work. The formula for calculating the energy stored in a battery is expressed as;

Energy stored=Power×Time

Energy stored = ΔV  * t  

where

ΔV is the change in velocity

t is the time

Substitute

Energy stored = 12.0 * 90.0

Energy stored = 1080 W.h

Total power consumed by the headlight = 2 * 36

Total power consumed by the headlight = 72Watts

Determine the time it takes to dischage

Time = Energy Stored/Power

Time = 1080/72

Time = 15hrs

Hence it will take the battery 15 hours to discharge completely.

Learn more on energy consumption here: brainly.com/question/24338873

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