What transforms electrical energy into mechanical energy?

Answer 1

An electric motor transforms electrical energy into mechanical energy. Electric motors have broad use throughout the world in the widest possible applications. Note that electric motors are not the only devices that convert electrical energy into mechanical energy, but they are far and away the most common ones. Another example would be a sonic or ultrasonic transducer used in sonar or sonography. Electrical energy stimulates a piezoelectric crystal, and the crystal converts the electrical energy into mechanical vibration.
Actually there are several ways to accomplish this little trick. However, the most common is probably the electric motor.

First, a little background: Every child knows how bar magnetics will push or pull each other depending on if like poles (push) or opposite poles (pull) are brought together. The next bit of knowledge is the fact that whenever an electric current flows, it produces, not only an electric field, but also a magnetic field. This is the source of the term "electromagnetic field" you may have heard about. I suspect by now you begin to see how this bit of magic works; simply concentrate this magnetic field by winding some wire into a coil, usually on a rotating shaft, provide an opposing field on one side and like field on the other and the shaft will rotate to try to align the opposing fields. Now you can use a mechanical system to switch the fields and the shaft will need to keep rotating to seek the opposing alignment again.

I'll leave the details for your research project but, effectively you have just made an electric motor!