We will be using a Saint Louis style of motor It consists of

We will be using a \"Saint Louis\" style of motor. It consists of a wire-wrapped iron core on an axis spindle. The wire ends are connected to a split-ring commutator. The split rotates between two fixed contacts as shown below: Electrons from the negative end of the battery pass through the lower fixed contact into the \"white\" half of the split-ring. From there they go into the coil, turning the coil into an electromagnet with, say, the square end of the coil behaving as a north magnetic pole and the round end behaving like a south magnetic pole. Half a rotation later the situation is as shown below: Connect the motor to a power supply set at a low setting. Note which direction the motor turns. Clockwise Explain, in detail, why the motor turns like this. Switch the direction of the current. Note what the motor does. Counter clockwise Explain, in detail, why the motor does this. Switch the poles of the magnets. Note what the motor does. Clockwise Explain, in detail, why the motor does this.

Solution

First I would try to explain the working of the St.Louis motor, so that you will able to understand while coming to the solution of the questions.

St. Louis motor works by the concept of induction, or inducing an electrical current from mechanical energy and vice versa. As an electrical current runs through a wire, it creates a magnetic field.

The bar magnets on the motor serve to attract and repel the induced magnetic field in the wire. As a result the motor spins.