A car radio draws 0.21 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

A car radio draws 0.21 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

College Physics

1st Edition

ISBN:9781938168000

Author:Paul Peter Urone, Roger Hinrichs

Publisher:Paul Peter Urone, Roger Hinrichs

Chapter20: Electric Current, Resistance, And Ohm's Law

Section: Chapter Questions

Problem 14CQ: The power dissipated in a resistor is given by P = V2/R, which means power decreases if resistance...

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