A wheel of mass 11 kg is pulled up a step by a horizontal rope as depicted in Figure P8....

A wheel of mass 11 kg is pulled up a step by a horizontal rope as depicted in Figure P8.81. If the height of the step is equal to one-third the radius of the wheel, what minimum tension is needed on the rope to start the wheel moving up the step? Hint: The wheel will start to move just as the normal force on the very bottom of the wheel becomes zero.