How Do You Calculate the EMF of a Cell in a Circuit?

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To calculate the EMF of a cell in a circuit, the total resistance must be determined by analyzing the configuration of resistors, both in series and parallel. The formula V=IR is used to find the voltage across branches, but this does not directly yield the EMF of the battery. The initial calculation yielded an EMF of 4.8V, which was deemed incorrect. A detailed step-by-step approach is necessary to clarify the process and ensure accurate results.
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Finding the EMF of the cell...

first post =)

Homework Statement


Find the EMF of the cell.
(diagram has been uploaded)



Homework Equations


Resistors is series : Rs= R1 + R2 + R3
Resistors in parallel: 1/Rp = 1/R1 + 1/R2 + 1/r3
V=IR

The Attempt at a Solution


Firstly i re-drew the circuit in a more simple form, to see what resistors are in parralel and which ones are in series. I then found the total resistance in the parralel circuit part that contained the 0.2A current. after that i used : V=IR.
My answer still seems incorrect as i got total EMF = 4.8V
 

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oooouftt said:
I then found the total resistance in the parralel circuit part that contained the 0.2A current. after that i used : V=IR.
That would tell you the voltage across that branch (and all parallel branches), but that's not the EMF of the battery.

Show exactly what you did, step by step.
 

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