Q. A 30 cm by 40 cm rectangular loop rotates at 130 rad/sec in a magnetic field 0.06Wb/metre sqre normal to the axis of rotation. If the loop has 50 turns, determine the induced voltage in the loop ? Attempt ! V(induced) in 1 turn = ∫(u X B).dS my vector u will be ρω in a∅ direction but i am unable to understand the direction of magnetic field what does it mean by direction perpendicular to axis of rotation ?