Currents, Resistance, and Power: Introduction

The filament in a light bulb provides resistance to the flow of electrons in the circuit.

The glow of a thin wire filament of a light bulb is caused by the electric current passing through it. Electric energy is transformed to thermal energy, which causes the wire’s temperature to become so high that it glows. Electric current and electric power in electric circuits are of basic importance in everyday life. In this section, we will examine current, resistance, and electrical power.