The Flexure Formula Learning Goal: To find the centroid and momentof inertia of an I-beams cross section, and to use the flexure formula to find the stress at a point on the cross section due to an internal bending moment. When a beam is subjected to an internal bending moment M (Figure 1), the stress distribution acting on a cross section can be related to the moment at that section and the geometric properties of the cross section using the flexure formula. The relationship can be written Mc in terms of the maximum stress, Omax where c is the perpendicular distance from the neutral axis to the farthest point in the section. It can also be written in terms of the vertical distance from the neutral axis, y My Figure 3 of 3 Consider an I-beam section with unequal flanges (Eigure 2).where w 9 in h 7.6 in. w2 5 in f 0.75 and w 1 in. The beam is subjected to a moment so that the internal moment on the section is about the 2-axis. Part A-Locate the centroid Since the widths of the two flanges are not the same, the centroid is not readily apparent. What is the distance from the bottom of the section to the centroid? (Figure 3) Express your answer with appropriate units to three significant figures. Value Units Subm Hints My Answers Give Up Review Part Part B Calculate the moment of inertia Once the position of the centroid is known, the moment of inertia can be calculated. What is the moment of inertia of the section for bending around the 2-axis? Express your answer to three significant figures and include the appropriate units. I Value Units Subm Hints My Answers Give Up Review Part Part C Maximum bending stress