In a Hartnell governor the mass of each ball is 2.5 kg. Maximum and minimum centrifugal forces on the balls are 2000 N and 100 N corresponding to radii 20 cm and 15cm respectively. Lengths of vertical and horizontal arms of the bell – crank levers are the same then what is the spring stiffness in N/cm?
(a) 100 (b) 200 (c) 400 (d) 800