Find the total magnetic induction at point O due to curved portion and straight portion.

What is a toroid? Calculate the magnetic induction at a point due to current in toroid.

The magnetic field at a point due to a current carrying conductor is directly proportional to

A bar magnet is 0.1 m long and its pole strength is 12 Am. Find the magnetic induction at a point on its axis at a distance of 0.2 m from its centre.

State Ampere's circuital law. By using it derive an expression for magnetic field intensity at a point due to a straight current carrying conductor.

A metallic wire carrying a current I is bent into the form as shown in the figure. The circular portion ABC of the wire is of radius r and the straight portion AC subtends an angle 2theta at the centre O. Find the magnetic field due to the conductor at point O. If the radius of the curved path is r, find the magnetic field at the centre O.