17) Which element having a projecting part of the cam imparts a reciprocating motion to the follower?

18) Which element of a cam is the distance one lobe will raise or lower the follower as the cam revolves?

19) Which is used to impart a reciprocating motion to the followers in a machine?

20) Calculate the lift of the plate cam that has a rise of 15 mm in 90 Degree rotation if the table lead screw has a pitch of 6mm.