Section B: Structure questions

1. A simply supported beam of a square cross-section of side 100mm with a uniform distributed loading of 5kN/m and a point load of 40kN is shown in the figure below.
a.) Calculate all reaction forces at A and B. (4 marks)
b.) Sketch the shear force and bending moment diagrams. (8 marks)
c.) Calculate the internal reactions at point C. (4 marks)
d.) Calculate the maximum bending stress at section C.

2. A shaft is made of an alloy having an allowable shear stress of τallow = 150 MPa.
a.) If the diameter of the shaft is 70 mm, determine the maximum torque T that can be transmitted. (6 marks)

b.) What would be the maximum torque T’ if a 15-mm-diameter hole were bored through the shaft? (7 marks)

c.) Using the torque T’ calculated in (b), determine the shear stress at the inner wall of the hollow shaft. (4 marks)

d.) Between (a) and (b), which dimension would you choose to construct a machinery, and why?