Question

Potential difference across a cell in the open circuit is 6 V. It becomes 4 V when a current of 2 A is drawn from it. The internal resistance of the cell is:

Hint:

The internal resistance of a cell affects the terminal voltage when a current is drawn. For parallel-connected identical cells, the total emf remains the same, but the internal resistance is reduced.

Answer 1

The internal resistance \( r \) is given by: \[ V = E - Ir \] Substituting the given values: \[ 4 = 6 - (2 \times r) \] \[ 2r = 2 \] \[ r = 1.0 \Omega \]