The correct answer regarding the terminal voltage of a battery is:
c. Terminal voltage is always less than the emf of the battery.
Explanation:
1. The electromotive force (emf) of a battery is the maximum voltage that the battery can provide when no current is flowing through it.
2. When a battery is connected to a circuit and current starts to flow, there is internal resistance within the battery that causes a voltage drop.
3. This voltage drop across the internal resistance results in the terminal voltage, which is the actual voltage available to the external circuit.
4. Therefore, the terminal voltage is always less than the emf of the battery due to this internal resistance.
In summary, the terminal voltage of a battery is always less than the emf of the battery because of the voltage drop across the internal resistance when current flows through the battery.
