The magnetic field produced by a current-carrying solenoid depends directly upon the strength of the current.

Draw the pattern of magnetic field lines through and around a current-carrying circular loop of wire. How would the strength of the magnetic field produced at the centre of the circular loop be affected if: $(i)$ the strength of the current passing through this loop is doubled? $(ii)$ the radius of the loop is reduced to half of the original radius?

What is the nature of the magnetic field produced by a straight current-carrying conductor? Explain with the help of an experiment.

In the below figure,$A$ and $B$ represent two straight wires carrying equal currents in a direction at right angles to the plane of paper inwards. Sketch separately the magnetic field lines produced by each current. Give a reason why the magnetic field at $K$ (mid-point of the line joining $A$ and $B$) will be zero.
What will be the effect on the magnetic field at $K$ if the current in wire $B$ is reversed?

How is the strength of the magnetic field at a point near a wire related to the strength of the electric current flowing in the wire?

State the energy change which takes place when a magnet is moved inside a coil having a galvanometer at its ends. Name this phenomenon.