Question

4. A rotating shaft is being subjected to two forces Fi = 40N and F2 = 70N. The shaft can rotate around the axis of A-B as shown. You can assume that the axis is frictionless for this question. (a) (1 mark) What is the effect of changing dimensions d, r, 0, and ø have on the net torque that wants to increase the angular acceleration of the disc? (b) (1 mark) Which way does the shaft rotating on the right side view? Clockwise or anti clockwise. You must give reasons for your answer to get marks for this question. (c) (2 marks) Compute the net torque on this system for d = 0.5 m, ø = 70°, r = 0.2 m, and 0= 45° A 0- Profile View Right Side View 3. (3 marks) The forces are shown in the members of the given truss. Identify the members of this truss which experience tension or compression; note that the truss members are labelled with small case letters. Identify any normal forces that present in this system. Explain the difference between forces of tension and compression. Use examples to illustrate your answer. Note that the forces shown on the diagram are forces exerted on the joints. b B A f C D E

Answer 1

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