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Energy conversion in motors

If the motor isn't accelerating then its KE doesn't increase

It would seem fairly uncontroversial that in a motor electrical energy is changed into movement ('kinetic') energy of the motor itself.

Try Why Do Astronauts Float by Julian Hamm

In fact this is only the case when the motor is speeding up from rest.  If the motor is spinning at constant speed then there is no increase in movement energy and all the electrical energy goes into doing whatever job the motor is doing.  In the case of a fan it would be moving the air.  With an electric lawnmower the electrical energy ends up heating the grass and the cutting blades.

back to Lesson 1: Electrical Energy