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

What is a toroidal solenoid?

The unit of magnetic induction is

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

Explain Biot-Savart law for the magnetic field produced at a point due to the current flowing in a current element. How will you determine the direction of the field?

What is electro-magnetic induction?