Explain how electric motors work.

Starting from the position shown in the diagram of the dc motor: 1)current in the left hand part of the coil causes a downward force, and current in the right hand part of the coil causes an upward force 2)the coil rotates anticlockwise because of the forces described above When the coil is vertical it moves parallel to the magnetic field, producing no force. This would tend to make the motor come to a stop, but two features allow the coil to continue rotating: 3)the momentum of the motor carries it on round a little 4)a split ring commutator changes the current direction every half turn Once the conducting brushes reconnect with the commutator after a half turn: 5)current flows in the opposite direction through the wire in the coil 6)each side of the coil is now near the opposite magnetic pole This means that the motor effect forces continue to cause anticlockwise rotation of the coil.