Question

A person is standing next to a current carrying wire which lies horizontally such that he is pointing in the direction in which the current is flowing. The magnetic field to the person’s right is in which direction?

• A. Vertically downwards
• B. Facing to his right
• C. Towards his back
• D. Facing to his left

Answer 1

The correct option is A Vertically downwards

For finding the direction of the magnetic field lines, we apply right-hand thumb rule.
According to this rule, imagine if we are holding a current carrying wire in your right hand so that the thumb points in the direction of the current, then the direction in which the fingers wrap the wire will represent the direction of magnetic field lines.
To the person’s right, the finger's curl would point vertically downwards, which is the direction of the magnetic field.