The displacement of the reciprocating roller follower, when it has contact with the straight flanks of the tangent cam, is given by (where r₁ = Minimum radius of the cam, r₂ = Radius of the roller follower, and θ = Angle turned by the cam from the beginning of the follower displacement)

A. (r₁ - r₂) (1 - cosθ)

B. (r₁ + r₂) (1 + cosθ)

C. (r₁ - r₂) [(1 - cosθ)/cos θ]

D. (r₁ + r₂) [(1 - cosθ)/cos θ]

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