Question

A 7.4 A current is set up in a circuit for 7.8 min by a rechargeable battery with a 3.0 V emf. By how much is the chemical energy of the battery reduced?

Answer 1

Answer:

10389.6 J

Explanation:

Power is the rate of doing work with respect to time, its S.I unit is in watts but it can also be expressed in J/s. Power is calculated using the formula:

$Power=\frac{energy}{time}$

Power is also the rate at which energy is used per second.

Energy is the capacity to do work and it is measured in joules (J).

Power = current × voltage = 7.4 A × 3 V = 22.2 W

$Energy=power*time\\\\time=7.8\ min=7.8*60\ s=468\ s\\\\Energy=22.2*468\\\\Energy=10389.6\ J$