The laws of electromagnetism tell us that energy can be transferred from one object to another:

$(a)$ 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?

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

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

State the direction of the magnetic field in the following case:

Explain with the help of a labelled diagram the distribution of magnetic field due to a current through a circular loop. Why is it that if a current-carrying coil has $n$ turns,the field produced at any point is $n$ times as large as that produced by a single turn?