Question

How EMF is measured?

Answer 1

EMF:

1. The EMF can be expressed in terms of the battery's internal resistance (r), $\epsilon =I\left(r+R\right)$.
2. We can then rearrange this in terms of terminal resistance using Ohm's law: $\epsilon =V+Ir$
3. For various resistances, the EMF of the cell can be determined by measuring the voltage across the cell with a voltmeter and the current in the circuit with an ammeter.