The strength of the magnetic field at a point r near a long straight current carrying wire is B. The field at a distance r/2 will be

An infinitely long straight conductor is bent into the shape as shown in the figure. It carries a current of i ampere and the radius of the circular loop is rmetre. Then the magnetic induction at its centre will be

The magnetic moment of a current carrying loop is 2.1 × 10^-25 amp × m² . The magnetic field at a point on its axis at a distance of  is

The earth's magnetic field at a certain place has a horizontal component 0.3 Gauss and the total strength 0.5 Gauss. The angle of dip is

The horizontal component of the earth's magnetic field is 0.22 Gauss and total magnetic field is 0.4 Gauss. The angle of dip. is

When a ferromagnetic material is heated to temperature above its Curie temperature, the material

In hydrogen atom, an electron is revolving in the orbit of radius 0.53 Å with 6.6 × 10¹⁵ rotations/second. Magnetic field produced at the centre of the orbit is

Four charges A, B, C, D are shown here, moving with equal speeds in a uniform magnetic field. Which charge experiences a maximum force?

A Metal Rod Pq (Carrying Current From P To Q) Is Placed Perpendicular To The Infinite Long Wire Carrying Current I₀. If This Arrangement Lies In A Horizontal Plane; Then The Rod Pq Will Rotate:

A coil having number of turns N and cross-sectional area A is rotated in a uniform magnetic field B with an angular velocity ω. The maximum value of the emf induced in it is