2.1 A heavy table is supported by flat steel legs (Fig. P2.1). Its natural period in lateral vibration is 0.5 sec. When a 50-lb plate is clamped to its surface, the natural period in lateral vibration...

Extracted text: 2.1 A heavy table is supported by flat steel legs (Fig. P2.1). Its natural period in lateral vibration is 0.5 sec. When a 50-lb plate is clamped to its surface, the natural period in lateral vibration is lengthened to 0.75 sec. What are the weight and the lateral stiffness of the table? Tn = 0.5 sec T = 0.75 sec Figure P2.1 2.2 An electromagnet weighing 400 lb and suspended by a spring having a stiffness of 100 lb/in. (Fig. P.2.2a) lifts 200 lb of iron scrap (Fig. P2.2b). Determine the equation describing the motion when the electric current is turned off and the scrap is dropped (Fig. P2.2c). (a) (b) Figure P2.2