The magnetic field produced in a straight conducting wire on passing the current through it is ............ .

Identify the type of magnetic fields represented by the magnetic field lines given below and name the type of conductors which can produce them.

$(a)$ What is meant by a 'magnetic field'?
$(b)$ How is the direction of magnetic field at a point determined?
$(c)$ Describe an activity to demonstrate the direction of the magnetic field generated around a current-carrying conductor.
$(d)$ What is the direction of the magnetic field at the centre of a current-carrying circular loop?

Explain what is short circuiting and overloading in an electric supply.

In the diagrams shown below:
$(i)$ Name the type of current in two cases.
$(ii)$ Identify any one source for each type of these currents.
$(iii)$ What is the frequency of current in case $(ii)$ in India?
$(iv)$ Use above graphs to write two differences between the current in two cases.

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