20.6.14
For a mechanical system with two generalized coordinates y and s, the kinetic energy is T = 0.7φ2 + 0.5 (s2 + (sφ2)) and the potential energy is P = -10 cosφ (1 + s), where s is in m; Φ is rad. Determine the acceleration s at the time when the angle φ = 0 and the angular velocity φ = 0. (Answer 10)