$A$ soft iron bar is introduced inside a current-carrying solenoid. The magnetic field inside the solenoid:

If the direction of current is reversed,the direction of magnetic field is also reversed.

Which scientist discovered that an electric current can be produced using a magnetic field?

With the help of a neat diagram,describe how you can generate induced current in a circuit.

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.

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?