A wheel with 10 metallic spokes each 0.5 m long, is rotated with a speed of 120 rpm. Please of the wheel is normal to earth's magnetic field at that place. If the magnitude of the field is 0.40 G, what is the induced emf between the axle and rim of the wheel?

A wheel with 8 matallic spokes each 50 cm long is rotated with a speed of 120 rev//mi n in a plane normal to horizontal component of earth's magnetic field. Earth's magnetic field at the phase is 0.4 G and angle of dip 60^(@) . Calculate the emf induced between the axle and rim of the wheel. How is the emf affected if number of spokes is increased ?

The horizontal component of earths's magnetic field at a place is 0.3 xx 10^-4T . If the angle of dip is 60^@ , what is the total earth's magnetic field?

A magnetic needle free to rotate about the vertical direction (compass ) point 3.5 west of the geographic north . Another magnetic needle free to rotate in a vertical plane parallel to the magnetic meridian has its north tip pointing down at 18^(@) with the horizontal . The magnitude of the horizontal component of the earth ' magnetic field at the place is known to be 0.40 G . what is the direction and magnitude of the earth's magnetic field at the place ?

A wire of length 0.1 m moves with a speed of 10 m s^-1 perpendicular to a magnetic field of induction 1 Wb m^-2 . What is the value of induced e.m.f.?

Metallic wire 1m in length is moving normally across a field of 0.1 T with a speed of 5 ms^-1 . Find the e.m.f between the ends of the wire.

A short bar magnet placed in a horizontal plane has its axis aligned along the magnetic north-south direction. Null points are found on the axis of the magnet at 14 cm from the centre of the magnet. The earth’s magnetic field at the place is 0.36 G and the angle of dip is zero. What is the total magnetic field on the normal bisector of the magnet at the same distance as the null-point (i.e., 14 cm) from the centre of the magnet? (At null points, field due to a magnet is equal and opposite to the horizontal component of earth’s magnetic field.)

When a wheel with metal spokes 1.2 m long rotates in a magnetic field of flux density 5 xx 10^(-5) T normal to the plane of the wheel, an e.m.f. of 10^(-2) V is induced between the rim and the axle. Find the rate of rotation of the wheel.