How is electric current defined?

Electric current is defined as the flow of electric charge. This definition emphasizes that current represents the movement of charged particles, typically electrons, through a conductive material. The flow of these charges is what allows electrical energy to be transmitted and used in various applications, such as powering devices and lighting.

To elaborate, the unit of electric current is the ampere, which is based on the amount of charge that passes through a given point in a circuit per unit time. This concept is fundamental to understanding electric circuits and how electrical components interact.

While the other options describe important concepts in electricity, they do not capture the essence of what electric current is. Resistance refers to how much a material opposes the flow of electric current but does not define what current itself is. Voltage, or electric potential, describes the energy per unit charge that drives the flow of current but is not the current itself. Power describes the rate at which energy is consumed or transferred in a circuit, but again, it does not characterize electric current. Therefore, identifying electric current as the flow of electric charge provides a clear and direct understanding of its nature in electrical systems.