1. ENT 153 TUTORIAL 1

2. Problem 1: The bar in Fig. 1 (a) has a constant width of 35 mm and a thickness of 10 mm. Determine the maximum average normal stress in the bar when it is subjected to the loading shown.
Note: Fig. 1 (b) shows the internal loadings of the members which are sectioned.
Fig. 1 (c) shows the normal force diagram representing the above results graphically.
These figures are not given in test or examination.

3. Problem 2: The 80-kg lamp is supported by two rods AB and BC as shown in Figure 2 (a). If AB has a diameter of 10 mm and BC has a diameter of 8 mm, determine the average normal stress in each rod.
Problem 3: The casting shown in Figure 3 (a) is made of steel having a
specific weight of γst = 80 kN/m3. Determine the average
compressive stress acting at points A and B.
Fig. 2
Fig. 3

4. Problem 4: Member AC shown in Fig
Problem 4: Member AC shown in Fig. 4 (a) is subjected to a vertical force of 3 kN. Determine the position x of this force so that the average compressive stress at the smooth support C is equal to the average tensile stress in the tie rod AB. The rod has a cross-sectional area of 400 mm2 and the contact area at C is 650 mm2.
Problem 5: The bar shown in Fig. 5 (a) has a square cross section for which the depth and thickness are 40 mm. If an axial force of 800 N is applied along the centroidal axis of the bar’s cross-sectional area, determine the average normal stress and average shear stress acting on the material along (a) section plane a-a and (b) section plane b-b.
Fig. 4
Fig. 5

5. Problem 6.

6. Problem 7:
The small block (Fig. 1) has a thickness of 5 mm. If the stress distribution at the support developed by the load varies as shown, determine
the force F applied to the block, and
the distance d to where it is applied.
Fig. 1