A steel ball of mass 1.4 kg is attached to a rope of negligible mass such that centre of gravity of the mass to the free end of the rope is 400 mm. If the mass rotated vertically about the free end. Determine:

a) the centrifugal force when the ball is rotated at 1960 prm,
b) the stress inducted in the rope if it's cross-sectional aria is 0.00035 m2
c) the rotational speed in rpm at which there is no tension in the rope