The displacement of a flat faced follower when it has contact with the flank of a circular arc cam, is given by (where R = Radius of flank, r₁ = Minimum radius of the cam, and θ = Angle turned through by the cam)

A. R (1 - cosθ)

B. (R - r₁) (1 - cosθ)

C. R (1 - sinθ)

D. (R - r₁) (1 - sinθ)

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