Topic : motional electromotive force

A circular wheel of 30 spokes is rotated at 400 rpm in a uniform magnetic field of 2 mT, length of each spokes is 0.25 m and magnetic field is along the axis of wheel, then the value of induced emf between rim and centre of wheel is

A train is moving with a speed of 20 m/s from North to South on the rails which are separated by 2 m. If the vertical component of earth's magnetic field at that place is 4 × 10⁻⁵ T, the emf induced across the axle of train is