Question

What will happen if we remove magnets from electric motor

Answer 1

Dear student,

If you remove the magnets from electric motor, the motor will stop working.
As the principle of electric motor is;
A current carrying conductor produces magnetic field around it. And whenever we place a current conducting wire in a external magnetic field, it experienced a force, and starts rotating.
The force experienced by current conducting wire placed in an external magnetic field is
$$\begin{gathered} F=I(L\times B) \\ F=force \\ I=current \\ L=lengthofwire \\ B=externalmagneticfield \end{gathered}$$
Due to this force, the armature coils start rotating (The direction of force can be directed by Fleming's left hand rule). If you remove the magnet from motor, the external magnetic force gets vanished (i.e. B=0), and F=0, and that's why the motors stops rotating.
That means the device can not convert electrical energy to mechanical energy.

Regards,