AY-18/19: QUESTION 3 (a) A uniform slender rod is bent into the shape as shown in Figure 3(a). It is 4 m long and has a
Posted: Thu May 05, 2022 6:03 pm
AY-18/19: QUESTION 3 (a) A uniform slender rod is bent into the shape as shown in Figure 3(a). It is 4 m long and has a mass of 4 kg. Show that its mass moment of inertia about 4 is given by 1A = 1.833 kgm² MA (b) This object is assembled into a mechanism as shown in Figure 3(b). It is hinged at point A, which is frictionless. The linear spring attached at the mid-point of AB has a spring constant k = 100 N/m, and an unstretched length of 0.5 m. Suppose it is released from rest at the position shown in the figure, determine the magnitude of velocity at point D when it is rotated by 90° counter-clockwise (i.e. DAB becomes horizontal) Take g = 9.81 m/s in your calculations. (c) Suppose you can add a point mass at either C or D to increase the velocity of D in part (b), which one will you choose. Explain your answer without doing the detail calculations. 1 m 1m Fixed wall 0.5 m 1m Figure 3(a) 00 8 1.0 m Figure 3(b)