# Back EMF equation, need help

#### Girn

1. Homework Statement
An A/C starter has a 12V supply & a back EMF of 6V. If the resistance is 0.1 ohms, calculate current during start-up & while in operation

2. Homework Equations
E=IR
Not sure what else? Sorry im stuck.

3. The Attempt at a Solution
Start up current
E=IR
12V=I x .01
I = 120A

operating current
6V=I x .01
I = 60A

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#### cnh1995

Homework Helper
Gold Member
Start up current
E=IR
12V=I x .01
I = 120A

operating current
6V=I x .01
I = 60A
Looks correct.

#### NascentOxygen

Mentor
An A/C starter has a 12V supply & a back EMF of 6V.
What is A/C an abbreviation for?

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