State Kirchhoff's current law.

State Kirchhoff's current law.

• A. The algebraic sum of voltages around a closed loop equals zero.
• B. The power in a circuit is conserved.
• C. The algebraic sum of currents entering a node equals the algebraic sum leaving it.
• D. The product of voltages around a loop is constant.

Answer: (C)

At a junction where multiple conductors meet, charge cannot accumulate in steady state, so the currents must balance. This means the total current flowing into the node equals the total current flowing out. In practice, you can assign a sign convention—take currents entering as positive and those leaving as negative—and the sum of all currents at the node should be zero. For example, if two currents enter a node with 2 A and 3 A, and a current leaves with 5 A, the balance is 2 + 3 − 5 = 0, showing current conservation at the node. This idea is what Kirchhoff's current law states. The other options describe different ideas: one is about voltages around a loop (Kirchhoff's voltage law), another is a general statement about power conservation (not the node-balance rule), and the last is not a standard circuit law.

At a junction where multiple conductors meet, charge cannot accumulate in steady state, so the currents must balance. This means the total current flowing into the node equals the total current flowing out. In practice, you can assign a sign convention—take currents entering as positive and those leaving as negative—and the sum of all currents at the node should be zero.

For example, if two currents enter a node with 2 A and 3 A, and a current leaves with 5 A, the balance is 2 + 3 − 5 = 0, showing current conservation at the node.

This idea is what Kirchhoff's current law states. The other options describe different ideas: one is about voltages around a loop (Kirchhoff's voltage law), another is a general statement about power conservation (not the node-balance rule), and the last is not a standard circuit law.