Statement (I): When a flat-faced follower is used, it would be preferable to provide an offset in the plane perpendicular to the plane of rotation of the cam.

Statement (II): Because of the offset, the follower is made to rotate continuously about its axis which in turn avoids jamming of the follower in its guide while moving up or down, reduces the wear of the follower flat surface and distributes the wear uniformly.

Concept:

Offsets are required in cam and followers to reduce wear and side thrust.

As in figure with offset‘d’, stroke length of follower will be less as compared to follower with zero offset. Less stroke length means follower movement will be less. Therefore, lesser reaction force to follower resulting in less wear and thrust as it will be uniformly distributed.

Thus, face cam are generally preferred with offset for the easy operation of cam.

Hence, both statement I and statement II are true and Statement (II) is the correct explanation of Statement (I).