Eli5 What causes motors to overheat when it’s facing more resistances than it can handle?
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Motors work through electromagnetic induction – a charging electric field inducing a changing magnetic field. But that principle happens in reverse too – a changing magnetic field induces an electric field, and as the motor is spinning, the coils moving through a magnetic field induces an electric field that opposes that of the power source and impedes the flow of current. The coils themselves in the motor have fairly little innate resistance.
So the motor is somewhat self-regulating, if it is connected to a heavier mechanical load and it starts to slow down, then the “back-EMF” gets weaker and its power draw increases. If the rotor is held in place while the motor is powered on, and it cannot overcome the load to start spinning at all, then there is very little electrical resistance and it can draw huge currents, enough to heat up the coils and potentially burn out the motor
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