A current flows downwards in a wire that passes vertically through a table top. Will the magnetic field lines around it go clockwise or anticlockwise when viewed from above the table?

If current flows downwards in a wire that passes vertically through a tabletop, the magnetic field lines around it will go clockwise when viewed from above the table. This is concluded by applying the right-hand thumb rule.

Explanation

The rule that is used for determining the direction of the magnetic field around a straight current-carrying conductor is Maxwell’s right-hand thumb rule.

According to the rule, the thumb points in the direction of the current, and the direction in which the fingers have surrounded the current-carrying conductor gives the direction of the magnetic field lines around the wire.