Question

what is the role of the split rings in an electronic motor

Answer 1

The Principle: It works on the principle of the magnetic effect of current. A current-carrying coil rotates in a magnetic field. Working: When a current is allowed to flow through the coil MNST by closing the switch, the coil starts rotating anti-clockwise. This happens because a downward force acts on length MN and at the same time, an upward force acts on length ST. As a result, the coil rotates anti-clockwise. Current in the length MN flows from M to N and the magnetic field acts from left to right, normal to length MN. Therefore, according to Fleming’s left hand rule, a downward force acts on the length MN. Similarly, current in the length ST flows from S to T and the magnetic field acts from left to right, normal to the flow of current. Therefore, an upward force acts on the length ST. These two forces cause the coil to rotate anti-clockwise. After half a rotation, the position of MN and ST interchange. The half-ring D comes in contact with brush A and half-ring C comes in contact with brush B. Hence, the direction of current in the coil MNST gets reversed. The current flows through the coil in the direction TSNM. The reversal of current through the coil MNST repeats after each half rotation. As a result, the coil rotates unidirectional. The split rings help to reverse the direction of current in the circuit. These are called the commutator.

Answer 2

Role of Split Ring in an Electric Motor

Split ring is used for reversing the direction of current in the coil. For the continuous rotation of the coil in the same direction, the current in the coil must be reversed. Therefore, after every half rotation of the coil the direction of the couple rotating the coil remains the same and the coil continues its rotation in the same direction.