Define the following terms as applied to cam with neat sketch.

(1) Pitch circle- Circle drawn from centre of cam through pitch points.

(2) Pressure angle- Angle between direction of follower motion and normal to pitch curve.

(3) Stroke- Maximum travel of follower from its lowest position to top most position.

(4) Module –(Gears) – Ratio of pitch circle diameter in mm to No. of teeth on gear.