An electron accelerates from rest in a horizontally directed field. the electron enters a magnetic field which steers it in a circle of radius 0.35mm. if the magnetic field is 0.23t, determine the potential difference required to accelerate the electron

The space between two 15-in.-long concentric cylinders is filled with glycerin (viscosity = 8.5 × 10-3 lb·s/ft2). the inner cylinder has a radius of 1 in. and the gap width between cylinders is 0.1 in. determine (a) the torque and (b) the power required to rotate the inner cylinder at 180 rev/min. the outer cylinder is fixed. assume the velocity distribution in the gap to be linear.