An electric current is a flow of electric charge through a conductor, such as a wire. It is measured in units of amperes (A) and is caused by the movement of electrons.
Electric currents and magnetic fields are closely related because an electric current creates a magnetic field and a changing magnetic field can induce an electric current. This phenomenon is known as electromagnetism.
Some common sources of magnetic fields include permanent magnets, electromagnets, and electric currents. The Earth also has a magnetic field due to its molten iron core.
Magnetic fields are measured using a device called a magnetometer. It can detect the strength and direction of a magnetic field and is often used in scientific research and navigation.
Electric currents and magnetic fields have numerous practical applications, such as generators and motors, which use the interaction between them to produce electricity and mechanical motion. They are also used in medical imaging, telecommunications, and transportation systems.