State the direction of the magnetic field inside the bar magnet.

Which of the following appliances does not have a lower power rating?

$A$ current-carrying solenoid behaves like a bar magnet.

An electron enters a uniform magnetic field at right angles to it as shown in the figure below. In which direction will this electron move? State the rule applied by you in finding the direction of motion of the electron.

$(a)$ What are magnetic field lines? How is the direction of a magnetic field at a point determined?
$(b)$ Draw two field lines around a bar magnet along its length on its two sides and mark the field directions on them by arrow marks.
$(c)$ List any three properties of magnetic field lines.

$(a)$ Describe an experiment with a diagram to show that force is exerted on a current-carrying conductor when placed perpendicular in a magnetic field.
$(b)$ How will this force change if the current in the conductor is increased?
$(c)$ Name a device that uses the above principle.