Question
What is the effective resistance of a car’s starter motor when 150 A flows through it as the car battery applies 11.0 V to the motor?
Question by OpenStax is licensed under CC BY 4.0
Final Answer

73.3 mA73.3\textrm{ mA}

Solution video

OpenStax College Physics, Chapter 20, Problem 20 (Problems & Exercises)

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Video Transcript
This is College Physics Answers with Shaun Dychko. The starter motor of a car draws 150 amps when it's being powered by the battery at 11.0 volts and the question is what is the effective resistance of the starting motor? So Ohm's law says that the voltage is current times resistance and so we can solve for R by dividing both sides by I and we get R then is voltage divided by current. So that's 11.0 volts divided by 150 amps which is 73.3 milliohms.