Question

A 5.0 V battery storing 43.0 kJ of energy supplies 1.5 A of current to a circuit. How much energy does the battery have left after powering the circuit for 1.0 hr?

Answer 1

Answer:

$E_{remain}=16kJ$

Explanation:

Given data

$V_{voltage}=5.0V\\I_{current}=1.5A\\E_{energy}=43.0kJ$

The Power is given as

$P_{power}=V_{voltage}I_{current}$

Substitute the given values

$P_{power}=5.0V*1.5A\\P_{power}=7.5W\\or\\P_{power}=7.5J/s$

In hour the energy is consumed is:

$E{_1}=7.5J/s*(3600s)\\E{_1}=27000J\\E{_1}=27kJ$

So the energy left after one hour is:

$E_{remain}=E_{energy}-E_{1}\\E_{remain}=43kJ-27kJ\\E_{remain}=16kJ$