Define the following terms commonly used in laying out the cam profiles:
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(i)
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Base circle
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(ii)
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Trace point
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(iii)
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Pitch curve
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(iv)
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Pressure angle
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The following notations refer to a Tangent cam with straight flank, circular nose and roller follower:
Rc = Base circle radius
Rr = Roller radius
Rn = Nose radius
a = Semiangle of action of the cam
b = Angle by which cam rotates for contact for roller with the flank
q = Any angle by which the cam has rotated
h = Lift or the stroke at an angle q
Draw a neat sketch of this cam. Determine the expressions for evaluating the lift (h), velocity (v) and the acceleration of the follower when the cam has turned through an angle q (which is less than b).