Corkscrew is a device that is used for pulling a cork from a bottle and consists of a spiral. The direction of the circular magnetic field lines can be given by Maxwell’s right-hand grip rule or Right handed cork screw rule. If a right-handed cork screw is rotated to advance along the direction of the current through a conductor, then the direction of rotation of the screw gives the direction of the magnetic lines of force around the conductor.
The right-hand screw rule, also known as cork screw rule, associates the direction of an electric current with the direction of the magnetic force lines circling the current.
The corkscrew rule is depicted in the figure, where the corkscrew is rotated downward into the cork. When the electric current runs straight down through the center of the corkscrew, the magnetic force lines are directed along the green line shown in the photograph.
If a right-hand cork screw is assumed to be held along the conductor, and screw is rotated such that it moves in the direction of the current, direction of the magnetic field is the same as that of the rotation of the screw.
Maxwell’s corkscrew rule states that imagines we are driving a corkscrew in the direction of the current then the direction in which handle turn directs the direction of the magnetic field lines.