The correct answer is: C. draw excessive current and overheat.
A single-phase induction motor has two windings: a main winding and a starting winding. The main winding is always connected to the power supply, while the starting winding is only connected for a short period of time during starting. The starting winding is connected in parallel with a capacitor, which creates a magnetic field that helps the motor to start. Once the motor is up to speed, the starting winding is disconnected from the power supply.
If the starting winding is left in the circuit, it will draw excessive current and overheat. This is because the starting winding is designed to be used for a short period of time only. When it is left in the circuit, it will continue to draw current even though it is not needed. This can cause the motor to overheat and damage the windings.
Here are brief explanations of each option:
- Option A: If starting winding of a single-phase induction motor is left in the circuit, it will run faster. This is not true. The starting winding is only connected for a short period of time during starting. Once the motor is up to speed, the starting winding is disconnected from the power supply. If the starting winding is left in the circuit, it will not cause the motor to run faster.
- Option B: If starting winding of a single-phase induction motor is left in the circuit, it will spark at light loads. This is not true. The starting winding is only connected for a short period of time during starting. Once the motor is up to speed, the starting winding is disconnected from the power supply. If the starting winding is left in the circuit, it will not cause the motor to spark at light loads.
- Option D: If starting winding of a single-phase induction motor is left in the circuit, it will run slower. This is not true. The starting winding is only connected for a short period of time during starting. Once the motor is up to speed, the starting winding is disconnected from the power supply. If the starting winding is left in the circuit, it will not cause the motor to run slower.