Question

a circuit has a voltage drop of 12.0 v across a 30.0 ω resistor that carries a current of 0.400 a. what is the power used by the resistor? use ( p = vi ).
a. 57.0 w
b. 4.80 w
c. 360.0 w
d. 12.0 w

Explanation:

Step1: Substitute values into formula

Given \(V = 12.0\space V\) and \(I=0.400\space A\), use \(P = VI\).
\(P=(12.0\space V)\times(0.400\space A)\)

Step2: Calculate power

\(P = 4.80\space W\)

Answer:

B. \(4.80\space W\)