9-30. Two channels (C 150 x 12) are welded together as shown in Figure P9-30. Determine the moment of inertia about both the x and y centroidal axes. For each channel I. = 13 1ine %3D 1, = 0.7 in. %3D X- y. 0.514" FIGURE P9-30 1.92"

If you take moments about A, do you have to include the moment AB in the calculation aswell. So the result would be BX-MBA-MAB?

in this question I dont understand how he found the distances ??? Sa and Sb , and why he done that for Sb  Sa = pi 88 why ???? why pi *88  Sb = pi 67 + 2 ( 88 - 67) ??why that please clarify for me that point

Brandon is trying to create a cool shelf bracket using pipes like he saw on Instagram. He is concerned about the pipe unscrewing from the wall bracket at A. He wants to know how likely it is that it will unscrew. Using some combination of drawings and written statements, answer the following questions. 1) What moment direction/axis would be critical to the pipe unscrewing at A? 2) Based on the current geometry, which force direction of F is most likely to create the moment described in part 1? 3) If the weight of the books acts only downwards, how could he modify his bracket so it cannot unscrew? You can use any combination of the parts shown (no need to use all of them). Show where the now vertical load F will be applied. Explain why your new design will be less likely to get unscrewed at A. x B 0.5 m 0.4 m A 0.3 m 0.3 m