Current flow in an electrical circuit is caused by voltage and opposed by what?

Current flow in an electrical circuit is primarily influenced by the presence of voltage, which acts as the driving force that pushes the current through the circuit. The flow of this electric current is opposed by resistance, which can be understood as the hindrance that the materials and components in a circuit provide to the passage of current.

Resistance arises due to the collisions of charge carriers, such as electrons, with the atomic structure of the material. This opposition to the flow of current is quantified in ohms and is a critical aspect in Ohm's Law, which is expressed as V=IR, where V is voltage, I is current, and R is resistance. As resistance increases, for a constant voltage, the amount of current that can flow through the circuit decreases.

In terms of the other concepts, power is a measure of the rate at which energy is consumed or converted in a circuit, and while it is related to voltage and current, it does not directly oppose current flow. Current does not oppose itself; rather, it is the measure of the flow itself. Capacitance relates to the storage of electric charge and influences how circuits respond to changes in voltage but does not directly oppose current flow like resistance does. Therefore, resistance is the correct answer, as