Explanation: Place several magnetic compass needles in a circle, around a conducting wire which can carry current. Provide a switch so that the current through the wire can be switched on and off. See picture below.

When the electric current moves through a wire, it makes a magnetic field. If you coil the wire around and around, it will make the magnetic force stronger, but it will still be pretty weak. Putting a piece of iron or steel inside the coil makes the magnet strong enough to attract objects.

Electric Current and Magnetic Fields Electric current produces a magnetic field. This magnetic field can be visualized as a pattern of circular field lines surrounding a wire. One way to explore the direction of a magnetic field is with a compass, as shown by a long straight current-carrying wire in.

An electric field (created by the potential difference between cathode and anode) is required in order for electrons to leave the cathode and create a current. The electron flow does not affect the electric field between the anode and cathode. That field depends only on the potential difference that is applied.

The electric current is the flow of charge per unit time. An electric field is the space around charged particle which it effects. Electric field lines are abstract; they simply show the space around a charged particle that will influence other charged particles.

The space surrounding a charged object is affected by the presence of the charge; an electric field is established in that space. A charged object creates an electric field – an alteration of the space or field in the region that surrounds it. Other charges in that field would feel the unusual alteration of the space.