Question

Assertion (A): When no current is drawn from a cell, the potential difference produced by the chemical reaction between the terminals of the cell is called its electromotive force.

Reason (R): When current is drawn from a cell, the potential difference between the electrodes of the cell is known as its terminal voltage.

Options

• Both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of Assertion (A).

• Both Assertion (A) and Reason (R) are true but Reason (R) is not the correct explanation of Assertion (A).

• Assertion (A) is false, but Reason (R) is true.

• Assertion (A) is true, but Reason (R) is false.

Answer 1

Both Assertion (A) and Reason (R) are true but Reason (R) is not the correct explanation of Assertion (A).

Explanation:

Assertion is true because the electromotive force (emf) is the potential difference of the cell when no current is drawn from it. The reason is also true because terminal voltage is the potential difference between the electrodes when current is drawn. However, the reason defines terminal voltage but does not explain why the open-circuit potential difference is called emf.