In an electric motor,the direction of current in the loop reverses after every $........$ rotation.

Describe an activity to show that the magnetic field produced by a given current in a wire decreases as the distance from the wire increases.

What is the direction of magnetic field lines inside a bar magnet?

$(a)$ 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 magnitude of an $AC$ voltage used in other countries like America $(USA)$ is $.........$ and its frequency is $.......$.

When an electric current flows through a conducting wire,what is produced in the region around it?