You get a summer job working with a construction company. You're placing the rafters for the roof, and your boss wants to place them as shown in the figure because it will require less wood. You think this is risky and would like to rotate each beam by 90 degrees, even though this will be more costly. a) Draw a FBD and calculate the internal moment throughout the beam as a function of x. Plot Mint as a function of x. b) Calculate the maximum normal stress caused by bending of the beam. At what point along the x axis does this occur? c) You estimate that the maximum normal stress each rafter can take without breaking is 3.5E7 Pa. Write a sentence or two to your boss explaining why he should follow your suggestion.

You get a summer job working with a construction company. You're placing the rafters for the roof, and your boss wants to place them as shown in the figure because it will require less wood. You think this is risky and would like to rotate each beam by 90 degrees, even though this will be more costly. a) Draw a FBD and calculate the internal moment throughout the beam as a function of x. Plot Mint as a function of x. b) Calculate the maximum normal stress caused by bending of the beam. At what point along the x axis does this occur? c) You estimate that the maximum normal stress each rafter can take without breaking is 3.5E7 Pa. Write a sentence or two to your boss explaining why he should follow your suggestion.

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