Question

What is the shape of the magnetic field lines at the centre of a current carrying circular ring?

• A. Magnetic field is zero at the centre
• B. Straight line
• C. Circular
• D. Ellipse

Answer 1

The correct option is B Straight line

The direction of magnetic field of every small section of the circular loop can be found by using the right hand thumb rule. At the centre the cumulative effect of all the field lines due to each small section is a straight line. The direction of magnetic field at the centre of circular coil is perpendicular to the plane of the coil. i.e. along the axis of the coil.