How Do You Calculate EMF with Ohm's Law?

AI Thread Summary
To calculate the electromotive force (emf) of a battery using Ohm's Law, the formula V = I(R + r) is applied, where R is the external resistance and r is the internal resistance. In this case, with an internal resistance of 0.15 ohms and a current of 1.5 A flowing through a 5.0-ohm resistor, the calculation yields an emf of 7.725 V. The method and answer presented appear to be correct based on the provided values. This approach effectively demonstrates the application of Ohm's Law in determining emf. Overall, the calculation is validated and accurate.
predentalgirl1
61
1
1.What is the emf of a battery with a 0.15-ohm internal resistance if the battery delivers 1.5 A to an externally connected 5.0-ohm resistor?








Given that r = 0.15 ohm , I = 1.5 ohm , R = 5 ohm.

By Ohm’s law V = I ( R + r)
= 1.5 (5.15)
E=7.725 V

Is my work/answer correct?
 
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Looks good to me.
 

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