Science Common Sense


1694 - How does a current-carrying wire in a magnetic field receive a force

Imagine you're holding a small magnet and moving it near a compass. The compass needle will move, right? That's because the magnet is creating a magnetic field around it.

Now, imagine you have a wire with electricity flowing through it, kind of like the magnet, but instead of creating a magnetic field, the electric current makes the wire act like a tiny magnet.

When this wire (the tiny magnet) is in a strong magnetic field, like the one from a big magnet or another coil of wire, the magnetic fields will interact. The big magnetic field will push or pull the tiny magnet (the wire) with a force.

The direction of the force depends on two things:

  1. The direction of the electric current flowing through the wire.
  2. The direction of the magnetic field around the wire.

If you remember the 'left-hand rule': point your thumb in the direction of the electric current, and your fingers in the direction of the magnetic field, your palm will point in the direction of the force!