You place a penny on a turntable at a distance of 14.3 cm from the center. the coefficient of static friction between the penny and the turntable is 0.400. the turntable's angular acceleration is 2.45 rad/s². how long after you turn on the turntable will the penny begin to slide off of the turntable? [note: assume the tangential component of friction is sufficiently small and can be ignored.]

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.