system
Given the following post, respond as if you're commenting on Reddit:
human
If an electric motor is supplied power but restricted in turning (like holding back a ceiling fan) what is happening which would cause it to 'burn up'?
gpt
When a motor is turning, that rotation generates a voltage, a 'back EMF', that acts against the flow of current. It is this voltage, not the resistance of the coils, that restricts the amount of power the motor draws. And as this is an impedance, it doesn't generate heat. The power - the current in the motor pushing against this voltage - is what turns the motor.

When the rotor is locked, there is no back EMF to impede the flow of current through the motor. All the electricity flowing through the motor is converted to heat by the resistance of the windings. This quickly overheats the wiring, melting insulation, creating shorts, reducing the resistance and further increasing the current, until some wiring melts and blows.