A battery charger is connected to a dead battery and delivers a current of 8.9 A for 4.7 hours, keeping the voltage across the battery terminals at 12 V in the process. How much energy is delivered to the battery?

1807.56 kJ

Explanation:

Parameters given:

Current, I = 8.9A

Time, t = 4.7hrs = 4.7 * 3600 = 16920 secs

Voltage, V = 12V

Electrical energy is given as:

E = I*V*t

Where I = Current

V = Voltage/Potential differenxe

t = time in seconds.

E = 8.9 * 12 * 16920

E = 1807056 J = 1807.056 kJ

1807056 J

Explanation:

Energy: This can be defined as the ability or the capacity to do work. The S. I unit of energy is Joules (J).

The expression for electric energy is given as,

Using,

E = VIt ... Equation 1

Where E = Electric Energy, V = Voltage, I = current, t = time.

Given: V = 12 V, I = 8.9 A, t = 4.7 hours = 4.7*3600 = 16920 s

Substitute into equation 1

E = 12 (8.9) (16920)

E = 1807056 J.

Hence the amount of energy delivered to the battery = 1807056 J