ERT2016 ENGINEERING MECHANICS 15 OCTOBER 2018 Question 1 a). A hoist trolley is subjected to the three forces shown in Figure 1a. Knowing that P-250 lb, determine: i. the required value of a if the resultant of the three forces is to be vertical, ii. the corresponding magnitude of the resultant force. P [10 marks] 400 lb 200 lb Figure la b). Determine by direct integration the centroid of the area shown in Figure 1b. Express your answer in terms of a and b. [10 marks] y=ka Figure 1b c). A system consists of a movable bin and its contents with a combined weight of 2.8 kN is shown in Figure 1c. Sketch the free body diagram and determine the shortest chain sling ACB that can be used to lift the loaded bin if the tension in the chain is not to exceed 5 kN. FI 0.7 m [5 marks] 1.2 m- Figure 1e Continued... 2/4