for a circular coil of radius R and N turns carrying a current I the magnitude of magnetic field at a point on its axis at a distance x from its centre is given by `B= (mu_0IR^2N)/(2(x^2+R^2)^(3/2)`
show that this reduces to the standard result for field at the centre of the coil.

For a circular coil of radius R and number of turns N carrying a current I, the magnitude of the magnetic field at a point on its axis at a distance x from its centre is given by B=(mu_(0)IR^(2)N)/(2(x^(2)+R^(2))^(3//2) Consider two parallel co-axis circular coils of equal radius R and number of turns N, carrying equal current in the same direction and separated by a distance R. Show that the field on the axis around the mid-point between the coils is uniform over a distance that is small compared to R and is given by B=0.72 mu_(0) NI//R , approximately. (Such an arrangement to produce a nearly uniform magnetic field over a small region is know as Helmholtz coils).

A circular coil of radius R carries an electric current i. The magnetic field at a point on the axis at a distance x from the centre of the coil (xgtgtR) varies as

A non conducting solid sphere of radius R is uniformly charged. The magnitude of electric field intensity due to the sphre at a distance r from its centre

A circular copper ring of radius r, placed in vacuum, has a charge q on it. Find out the electric fields on the axis of the ring at a distance x from its centre. ?

A circular coil of radius r carries a current I . It produces magnetic fields B_(1) at the centre of the coil and B_(2) at an axial point at a distance r from the centre. The ratio of B_(1) and B_(2) is

A circular coil A is of radius R and current I, another circular coil 'B’ is of radius 2R and current 2I.The ratio of magnetic field B_A : B_B at their centre is—

A circular coil of radius 0.01 m has 100 turns and a current 7A. It is suspended freely in a magnetic field 0.2 T. Which position of it will be be in stable equilibrium.

If we double the radius of a current carrying coil keeping the current unchanged, the magnetic field at its centre will