State and explain Maxwell’s right- hand thumb rule.

Hint: The right-hand rule was given by Maxwell and this indicates the magnetic field’s direction when the direction of the current in the current carrying conductor. The whole law can be explained by grasping the current carrying conductor in a right hand.

Complete step by step answer:
In order to explain Maxwell's right hand thumb rule, imagine that you are holding the current carrying wire in your right hand such that the thumb points up and all the other fingers grasp the wire. The thumb points the direction of the current flow through the conductor and the fingers surrounding the conductor points the direction of the magnetic field lines that are perpendicular to that of the current.

For the deep understanding of the concept, let us consider the straight current carrying conductor $AB$ which is vertically held and the point $A$ is located down and the point $B$ is located upside of the conductor. Let us imagine holding the conductor, such that the thumb points the current, so the current moves to the point $B$ from $A$ . And the grasping fingers denotes the magnetic field around the conductor $AB$. This direction of the magnetic field is anticlockwise. Since the right hand is considered for understanding this rule, it is known as the right hand thumb’s rule.

Note: On the reverse of the above considered case, when the thumb holding the conductor points downwards, then the magnetic field around the current carrying conductor will be clockwise. So remember that it may be clockwise and the anticlockwise that solely depends on the direction of current.