Mention the special feature regarding the shape of magnetic field lines.

What is a fuse? How does it function?

$(a)$ Describe an activity to draw a magnetic field line outside a bar magnet from one pole to another.
$(b)$ List any two properties of magnetic field lines.

$(a)$ Draw a schematic labelled diagram of a domestic wiring circuit which includes $(i)$ a main fuse,$(ii)$ a power meter,$(iii)$ one light point,and $(iv)$ a power plug.
$(b)$ Why is it necessary to connect an earth wire to electric appliances having metallic covers?

The direction of the magnetic force acting on a current-carrying wire placed in a strong magnetic field can be determined by which rule?

Whenever the magnetic field through a coil is changed,a potential difference is produced in the coil.