Which of the following properties of a proton can change while it moves freely in a magnetic field?

List the properties of magnetic field lines.

Choose the correct option.
The magnetic field inside a long straight solenoid carrying current

When does an electric short circuit occur?

Two circular coils $A$ and $B$ are placed close to each other. If the current in the coil $A$ is changed,will some current be induced in the coil $B$? Give reason.

State the rule to determine the direction of: $(i)$ a magnetic field produced around a straight current-carrying conductor,$(ii)$ force experienced by a current-carrying straight conductor placed in a magnetic field perpendicular to it,and $(iii)$ current induced in a coil due to its rotation in a magnetic field.