The correct answer is option 'C' - the current induced in the rotor conductor of a 3-phase squirrel cage induction motor is nearly equal to the rated current. Let's delve into the details to understand why this is the case.

Electric Motors:
Electric motors are devices that convert electrical energy into mechanical energy. They are widely used in various applications such as pumps, fans, compressors, and industrial machinery. Three-phase squirrel cage induction motors are one of the most commonly used types of electric motors.

Squirrel Cage Induction Motor:
A squirrel cage induction motor consists of two main parts - the stator and the rotor. The stator is the stationary part of the motor and is made up of three sets of windings placed 120 degrees apart. These windings are connected to a three-phase power supply.

The rotor is the rotating part of the motor and is made up of laminated iron cores with conductive bars or "squirrel cage" conductors placed in slots. When the motor is connected to a three-phase power supply, a rotating magnetic field is created in the stator windings.

Induced Current in the Rotor:
The rotating magnetic field in the stator induces a current in the rotor conductors through electromagnetic induction. This induced current creates a magnetic field in the rotor, which interacts with the stator magnetic field, causing the rotor to rotate.

The magnitude of the induced current in the rotor depends on several factors, including the design of the motor, the load on the motor, and the slip of the motor. Slip is the difference between the synchronous speed of the rotating magnetic field and the actual speed of the rotor.

Under Full Load:
At full load, the slip of the motor is relatively small, which means that the rotor speed is close to the synchronous speed. As a result, the induced current in the rotor is nearly equal to the rated current.

This is because at full load, the motor is designed to operate at its maximum capacity. The motor windings and the rotor conductors are sized to handle the rated current without overheating. Therefore, the induced current in the rotor is designed to be nearly equal to the rated current to ensure efficient and reliable motor operation.

In summary, at full load, the current induced in the rotor conductor of a 3-phase squirrel cage induction motor is nearly equal to the rated current. This ensures that the motor operates efficiently and reliably under maximum load conditions.