In a series circuit, what is true about the current?

In a series circuit, the defining characteristic of the current is that it remains constant at every point in the circuit. This is a result of the principle of conservation of charge, which states that charge cannot be created or destroyed; it only flows through the circuit. As the same charge passes through each component in the circuit, the amount of current, defined as the flow of electric charge, does not change.

Thus, since there are no alternate pathways for the current to take (as there would be in a parallel circuit), every component—the resistors, the battery, etc.—has the same current flowing through it. This uniformity ensures that the voltage drops across each component add up to the supply voltage, but the current itself remains constant throughout.

This understanding is crucial for analyzing and designing electrical circuits, as it helps predict how changes in one part of the circuit will affect the overall behavior of the system.