Does current vary in a series circuit?

Does current vary in a series circuit?

• A. Yes; it changes along the circuit
• B. No; it remains constant throughout
• C. Only at the power source does it change
• D. No, the current is the same at all points in the circuit

Answer: (D)

Current is the rate at which electric charge flows. In a series circuit there is only one path for that flow, so the same amount of charge per second passes through every component. Because charge can’t pile up at a point in a steady state, the current must be the same at all points along the path. What changes in a series circuit is how the voltage is distributed: the voltage drops across each component add up to the source voltage, while the current stays constant. If the circuit is opened, current stops everywhere along the path. In contrast, current would differ in circuits with branching (parallel paths) where it splits among branches.

Current is the rate at which electric charge flows. In a series circuit there is only one path for that flow, so the same amount of charge per second passes through every component. Because charge can’t pile up at a point in a steady state, the current must be the same at all points along the path. What changes in a series circuit is how the voltage is distributed: the voltage drops across each component add up to the source voltage, while the current stays constant. If the circuit is opened, current stops everywhere along the path. In contrast, current would differ in circuits with branching (parallel paths) where it splits among branches.