You push a 4.9 kg block against a horizontal spring, compressing the spring by 16 cm. then you release the block, and the spring sends it sliding across a tabletop. it stops 77 cm from where you released it. the spring constant is 220 n/m. what is the coefficient of kinetic friction between the block and the table?

Wo small variable-thrust jets are actuated to keep the spacecraft angular velocity about the z-axis constant at ? 0 = 1.16 rad/s as the two telescoping booms are extended from r1 = 1.18 m to r2 = 4.69 m at a constant rate over a period of 124 seconds. the small 19-kg experiment modules at the ends of the booms may be treated as particles, and the mass of the rigid booms is negligible. determine the necessary thrust t for each jet as a function of time where t = 0 is the time when the telescoping action is begun. after you have the general expression for t, answer the questions. show work.