What is the term for a cylindrical coil of wire that becomes electromagnetic when current flows through it?

The term for a cylindrical coil of wire that becomes electromagnetic when current flows through it is a solenoid. A solenoid functions based on the principle that when an electric current passes through the coiled wire, it generates a magnetic field around it. This magnetic field can then interact with other magnetic materials or can be used to create mechanical movement, which is essential in various applications like electromagnets, relays, and magnetic switches.

In contrast, a capacitor stores electrical energy in an electric field and does not produce a magnetic field when current flows; it's primarily used for smoothing or filtering signals in circuits. A motor converts electrical energy into mechanical energy, but it operates on the principle of electromagnetism in conjunction with magnetic fields and is typically more complex than just a coil. Lastly, a resistor is designed to limit the flow of electrical current, converting electrical energy into heat, and does not generate a magnetic field when current flows through it.