Question

Emf of a cell is ______ the terminal voltage when the cell is in open circuit.

Options

• greater than

• less than

• equal to

Answer 1

Emf of a cell is equal to the terminal voltage when the cell is in open circuit.

Explanation:

In an open circuit, a cell's Electromotive Force (EMF) is equal to its terminal voltage, as no current is present, resulting in no voltage drop across the cell’s internal resistance. In a closed circuit where current is drawn, the terminal voltage (V) decreases relative to the electromotive force (EMF) (E) due to internal resistance (r), as articulated by the equation:

V = E − Ir