A Whitworth quick return motion mechanism, as shown in Fig. 5.38, has the following particulars : Stroke length P R2 R R1 A D Line of stroke P2 A2 Fig. 5.38 Time of cutting stroke Length of stroke = 150 mm ; Driving crank length= 40 mm; Time of return stroke Find the lengths of CD and PD. Also determine the angles a and B. (Hint : Length of stroke - R,R, PP, 2PD) JAns. 20 mm, 75 mm; 240, 120| A.