Ace the BMAT 2025 – Unleash Your Biomedical Superpowers!

The role of a battery in a circuit is to provide a source of voltage. A battery converts chemical energy into electrical energy, and this process enables it to create an electric potential difference between its terminals. This potential difference is what drives the flow of electric current through the circuit when the circuit is closed.

When a battery is connected to a circuit, it establishes the necessary voltage that pushes electrons through the conductive paths, allowing devices or components within the circuit to function. The magnitude of the voltage output from the battery determines how much current can flow, based on the resistance present in the circuit according to Ohm's Law (V = I × R).

The other options pertain to different roles within a circuit. Resistance is a property of components that limits current flow, changing current direction is typically the role of devices such as switches or diodes, and acting as a load refers to components that consume electrical power, such as bulbs or motors. However, the primary and defining function of a battery is to supply the voltage necessary for the circuit to operate.