magnetic effect of electric current

Magnetic effect of electric current is the production of a magnetic field around a conductor when electric current flows through it.

• A current-carrying wire behaves a little like a magnet: it can affect a nearby compass needle even though the wire itself may not look like a magnet.
• The magnetic field forms all around the wire. If the current stops, this field disappears, unlike the magnetism of a permanent bar magnet.
• The effect becomes stronger when more current flows through the wire. Coiling the wire into loops can make the magnetic effect much stronger too.
• Think of electric current as moving water in a pipe: although the water flows inside the pipe, it can create effects around it. Similarly, moving electric charges in a wire create a magnetic influence around the wire.
• This link between electricity and magnetism allows us to make useful devices such as electromagnets, motors, electric bells, and loudspeakers. It is one of the most important ideas behind modern electrical technology.