Question

A car radio draws 0.32 A of current in the auto's 12-V electrical system.(a) How much electric power does the radio use? _________W(b) What is the effective resistance of the radio? _________Ω

Answer 1

a)

The power is given by:

`P=VI`

Where V is the voltage and I is the current.

In this case the voltage is 12 V and the current is 0.32, then we have:

`\begin{gathered} P=(12)(0.32) \\ P=3.84 \end{gathered}`

Therefore, the power is 3.84 W

b)

Ohm's law states that:

`R=(V)/(I)`

Then we have:

`\begin{gathered} R=(12)/(0.32) \\ R=37.5 \end{gathered}`

Therefore, the resistance is 37.5 Ohms