Write the equation for the magnetic field at the centre of the circular coil carrying current.

How can one reverse the direction of magnetic field produced at the centre of a circular coil carrying electric current?

The magnetic field field produced at the centre of a circular coil carrying a current is 0.005T. Will the magnetic field change if both the number of turns and the current are doubled? (write yes or no)

Magnetic field at the centre of a semicircular coil of N turns and radius r carrying current I is ______(Fill in the blank)