2. A cam, with a minimum radius of 25 mm, rotating clockwise at a uniform speed is to be designed to give a roller follower, at the end of a

valve rod, motion described below : 1. To raise the valve through 50 mm during 120° rotation of the cam; 2. To keep the valve fully raised through next 30°B 3. To lower the valve during next 120°; and 4. To keep the valve closed during rest of the revolution i.e. 90° ;