Suggested languages for you:

Americas

Europe

Q20PE

Expert-verifiedFound in: Page 733

Book edition
1st Edition

Author(s)
Paul Peter Urone

Pages
1272 pages

ISBN
9781938168000

**What is the effective resistance of a car’s starter motor when \({\bf{150}}\;{\bf{A}}\) flows through it as the car battery applies \({\bf{11}}{\bf{.0}}\;{\bf{V}}\) to the motor?**

The effective resistance of the car’s starter motor is \(0.073\;{\rm{\Omega }}\).

The given data can be listed below as,

- The value of current flow is, \(I = 150\;{\rm{A}}\).
- The potential difference of the battery is, \(V = 11.0\;{\rm{V}}\).

**According to Ohm's law, the value of potential difference across a specific electrical circuit is directly proportional to the electrical current flow. The proportionality constant in this relationship is the circuit element's resistance.**

The expression to calculate the effective resistance of the car’s starter motor is expressed as,

\(\begin{align}V = IR\\R = \frac{V}{I}\end{align}\)

Here, \(R\) is the effective resistance of the car’s starter motor.

Substitute all the known values in the above equation.

\(\begin{align}R = \left( {\frac{{11.0\;{\rm{V}}}}{{150\;{\rm{A}}}}} \right)\\ \approx 0.0733\;{\rm{V/A}}\\ \approx \left( {0.0733\;{\rm{V/A}}} \right)\left( {\frac{{1\;{\rm{\Omega }}}}{{1\;{\rm{V/A}}}}} \right)\\ \approx 0.073\;{\rm{\Omega }}\end{align}\)

Thus, the effective resistance of the car’s starter motor is \(0.073\;{\rm{\Omega }}\).

94% of StudySmarter users get better grades.

Sign up for free