Question

“A high voltage battery must have a large internal resistance.” Justify.

Answer 1

The total voltage provided by a battery is given by:

V = E − Ir

Where all the alphabet are in their usual meanings. From Ohm’s law:

I = `E/((R + r))`

Where R is the external resistance.

A battery with a strong electromotive force (E) and large internal resistance (r) restricts the current (I). This mitigates excessive current flow, which could otherwise result in overheating, energy dissipation, or circuit damage. An elevated internal resistance ensures a consistent, regulated current supply, making the battery safe for delicate applications.