1. The uniform rod ABC weighs 5 lb, and is attached to wo springs as shown. If end C is given a small displacement and released, determine the frequency of vibration of the rod. Use Energy Method. k = 3 lbg/in. k = 4 lbg/in. C 15 in. 15 in.

The 20-1b rectangular plate has a natural period of vibration t = 0.4 s, as it oscillates around the axis of rod AB. Neglect the mass of the rod. Suppose that a = 3 ft, b = 5 ft. (Figure 1) Figure A 1 of 1 Part A Determine the torsional stiffness k of the rod, measured in lb. ft/rad. Express your answer in pound-feet per radian to three significant figures. ΠΑΣΦ k = Submit Provide Feedback ↓↑ vec Request Answer lb-ft/rad

Three (very small) beads with masses m, m, and u can slide without friction on a (very thin) fixed ring of radius a and are connected to each other by (weightless) springs of equal stiffness k and equilibrium length 1 = √3a. Find the normal frequencies and normal modes of vibration for this system. Interpret the physical meaning of the modes you have found. m wwwww. mu k,l wwww. k, I m

Which one is correct please?