The figure shows a system in which an inextensible cable passes over a frictionless pulley, with inertia 0.25 kgm and a radius of 0.1m, to lift a box of mass 5 kg. At the instance shown, the box is accelerating upwards at 0.2 m/s. What force, F, must have been applied to the cable to cause this acceleration? There is no slip between the cable and the pulley. A free body diagram has been provided to assist workings. Gravity can be assumed to be 10 m/s. 60 F+ Ry R mpg T T 5kg a = 0.2 m/s mBg a