A uniform magnetic field B(f), pointing upward fills a circular region of radius, s in horizontal plane. If B is changing with time, find the induced electric field

If B_1 is the magnetic field induction at a point on the axis of a circular coil of radius R situated at adistance R sqrt 3 and B_2 is the magnetic field at the centre of the coil, then ratio of B_1/B_2 is equal to

The magnetic field on the axis of a circular current carrying conductor of radius r at a distance r from centre is B_(a) and the magnetic field at its centre is B_(c ) . The value of B_(a) : B_(c ) is

A proton enters a perpendicular uniform magnetic field B at origin along the positive x axis with a velocity V as shown in the figure. Then it will follow the following path. [The magnetic field is directed into the paper]

A photon of energy E ejects a photoelectron from a metel surface whose work function is phi_(0) . If this electron enters into a unifrom magnetic field of induction B in a direction perpendicular to the field and describes a circular path of radius r, then the radius r, is given by, (in the usual notation)

A short bar magnet with its north pole facing north forms a neutral point at P in the horizontal plane. If the magnet is rotated by 90^(@) in the horizontal plane, the net magnetic induction at P is (Horizontal component of earth's magnetic field =B_(H))

A coil of 100 turns each of area 0.12m^2 is rotated with constant speed 62.8rad/s in uniform magnetic field of induction 0.02 tesla about an axis in the plane of coil and perpendicular to the direction of field. Calculate maximum value of induced e.m..f.in the coil.

A circular loop of radius 'r' of conducting wire connected with a Voltage source of zero internal resistance produces a magnetic field 'B' at its centre. If instead, a circular loop of radius '2r' made of same material, having the same cross section is connected to the same voltage source, what will be the magnetic field at its centre?

A rectangular coil 20cmxx20cm has 100 turns and carries a current of 1 A . It is placed in a uniform magnetic field B=0.5 T with the direction of magnetic field parallel to the plane of the coil. The magnitude of the torque required to hold this coil in this position is