What will happen if we give 60hz supply to a 50hz rated induction motor?

If you give a 60Hz supply to a 50Hz rated induction motor, it's like asking a sloth to keep up with a cheetah at a marathon. The motor will try to keep up, but it won't be able to match the speed of the new supply frequency. 

This mismatch in frequency can lead to several consequences:

1. Increased speed: The motor will spin faster, about 20% faster than its rated speed. This could be a problem if the motor is connected to a mechanical load that can't handle the increased speed.

2. Reduced torque: The motor's torque will decrease proportionally to the frequency increase. This means the motor will have less "oomph" to drive the load.

3. Overheating: The motor will draw more current to compensate for the reduced torque, leading to increased heat generation. This can shorten the motor's lifespan and potentially cause it to fail prematurely.

4. Increased vibration: The motor may vibrate more due to the mismatch between the rotor and stator magnetic fields.

In short, it's like trying to fit a square peg into a round hole. It might work, but it's not ideal and could lead to problems down the line.