What happens if a full circular ring is used instead of a split ring (commutator) in an electric generator?

Which of the following devices is used for producing electric current?

What is a solenoid? Draw the magnetic field lines for a solenoid and a bar magnet. Compare the two and state one similarity.

The diagram below shows a circuit containing a coil wound over a long and thin hollow cardboard tube. Copy the diagram and:
$(i)$ Show the polarity acquired by each face of the solenoid.
$(ii)$ Draw the magnetic field lines of force inside the coil and also show their direction.
$(iii)$ Mention two methods to increase the strength of the magnetic field inside the coil.

$A$ device used for producing current is:

The device used for producing electric current is called a