In the right-hand rule, the thumb points in the direction of the current. What do the fingers indicate?

In the right-hand rule, the thumb points in the direction of the current. What do the fingers indicate?

• A. Direction of current
• B. Direction of magnetic field
• C. Direction of magnetic force
• D. Direction of electric field

Answer: (B)

The right-hand grip rule shows how current creates a magnetic field. With your thumb pointing along the conventional current, the way your fingers wrap around the wire gives the direction of the magnetic field lines around the conductor. The magnetic field forms circles around the wire, so the fingers point along the tangent to those circles at each point. If the current points upward, the fingers curl counterclockwise when viewed from above, indicating the magnetic field direction. If the current reverses, the magnetic field direction reverses too. This is about the magnetic field, not the electric field, and the force on a moving charge comes from a different rule that involves velocity as well as the magnetic field.

The right-hand grip rule shows how current creates a magnetic field. With your thumb pointing along the conventional current, the way your fingers wrap around the wire gives the direction of the magnetic field lines around the conductor. The magnetic field forms circles around the wire, so the fingers point along the tangent to those circles at each point. If the current points upward, the fingers curl counterclockwise when viewed from above, indicating the magnetic field direction. If the current reverses, the magnetic field direction reverses too. This is about the magnetic field, not the electric field, and the force on a moving charge comes from a different rule that involves velocity as well as the magnetic field.