Question

The current going through a car starter is 210 A. If the battery maintains 12 V across the motor, how much electrical energy is delivered to the starter in 10.0 s?Question 28 options:25 J250 J2.5 102 J2.5 104 J

Answer 1

We are given the following information

Current = 210 A

Voltage = 12 V

Time = 10 s

The electrical energy delivered to the starter is given by

$E=I^2\cdot R\cdot t$

Where I is current, R is the resistance, and t is the time.

First, let us find the resistance.

$R=\frac{V}{I}=\frac{12}{210}=\frac{2}{35}\; \Omega$

So, the resistance is 2/35 ohms.

$\begin{gathered} E=I^2\cdot R\cdot t \\ E=210^2\cdot\frac{2}{35}\cdot10 \\ E=25200\; J \end{gathered}$

Therefore, the electrical energy delivered to the starter is 25200 J