How Do You Calculate EMF in a Circuit with a Resistor?

AI Thread Summary
To calculate EMF in a circuit with a resistor, the relationship between current (I), resistance (R), and EMF can be expressed using the equation I = e/(r + R). The discussion clarifies that if the problem is asking for voltage, it can be calculated using P = I^2R or P = V^2/R, resulting in a voltage of 54.8V. It is noted that in cases where a battery has no internal resistance, the EMF is equivalent to the voltage. Ultimately, the conclusion is that the voltage (V) is indeed the EMF in this scenario. Understanding these relationships is crucial for solving circuit problems involving resistors and EMF.
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Homework Statement


The question itself doesn't make sense to me, it says to find emf but the answer box has V=
?
problem is an attachment.


Homework Equations


I=e/(r+R)
Ir+IR=emf
P=VI


The Attempt at a Solution


If it wants voltage that's simple P=I^2R P=V^2/R V=54.8V if it wants emf I need some pointers ... Thanks for any help
 

Attachments

  • PF.png
    PF.png
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Dont worry - - solved V is emf
 
Here emf is the voltage difference
 
If a battery has no internal resistance, its EMF and its voltage are the same thing.
 

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