Which trio is required for current to flow through a conductor?

Which trio is required for current to flow through a conductor?

• A. Source of current, something to transport it, and something that causes current to flow
• B. A switch, a fuse, and a resistor
• C. A battery, a wire, and a lamp
• D. A magnet, a coil, and a diode

Answer: (A)

Current can only flow when there is a complete circuit: a source of electrical energy to push charges, a conducting path to carry them, and a load that uses the energy, completing the loop. The source provides the driving force (voltage), the wires serve as the transport medium, and the load (such as a lamp or other device) is what causes current to flow by consuming the energy. If any one of these elements is missing, the circuit isn’t closed or the driving force isn’t present, so current cannot flow. The described trio directly captures this requirement by naming the energy source, the conducting path, and the device that uses the energy.

Current can only flow when there is a complete circuit: a source of electrical energy to push charges, a conducting path to carry them, and a load that uses the energy, completing the loop. The source provides the driving force (voltage), the wires serve as the transport medium, and the load (such as a lamp or other device) is what causes current to flow by consuming the energy. If any one of these elements is missing, the circuit isn’t closed or the driving force isn’t present, so current cannot flow. The described trio directly captures this requirement by naming the energy source, the conducting path, and the device that uses the energy.