In an electric motor, the direction of current in the coil changes once in each:

What is an electric motor? With the help of a labelled diagram, describe the working of a simple electric motor.

What are the special features of commercial electric motors?

An electron beam enters a magnetic field at right angles to it as shown in the Figure.

The direction of force acting on the electron beam will be:

The force experienced by a current-carrying conductor placed in a magnetic field is the largest when the angle between the conductor and the magnetic field is: