What happens in an open circuit?

• A. The electrical current flows.
• B. Voltage remains constant.
• C. Current is interrupted and does not flow.
• D. The load resistance drops to zero.

Answer: (C)

An open circuit has a broken path, so there’s no complete loop for current to travel. Because the loop isn’t closed, current cannot flow; according to I = V/R, the effective resistance is essentially infinite, which makes the current zero. The voltage from the source can still appear across the open gap, but no current is delivered to any load because the path is interrupted. The other statements describe conditions you’d see in a closed loop or misunderstand the resistance: current does not flow, the load resistance does not drop to zero—in an open circuit the path behaves as if the resistance were infinite, and while the source may maintain a specified voltage, that alone doesn’t cause current to flow without a closed path.