The potential difference across a cell is 1.8 V when a current of 0.5 A is drawn from it. The p.d. falls to 1.6 V when a current of 1.0 A is drawn. Find the emf and the internal resistance of the cell.

Solve the equations:
1.8= E - 0.5R...(1
1.6= E - 1.0R...(2
You will get R=0.4 ohm after cancelling out 'E' in both the equations.
Substituting R=  0.4 in eq. 1), we get
1.8= E - 0.2
E= 2V
Hope it helps and this is the correct answer
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