Meriam, Kraige & Bolton — Kinematics of Particles: Problem 2_120

2/120 For the fireworks shell of Prob. 2/119, determine the values of \(\ddot{r}\) and \(\ddot{\theta}\) when the shell reaches an altitude \(y = 175 \text{ ft}\). Refer to the printed answers for Prob. 2/119 as needed. (Context from Prob. 2/119: A fireworks shell \(P\) is launched upward from point \(A\) and explodes at its apex at an altitude of \(275 \text{ ft}\). Relative to an observer at \(O\), determine the values of \(\dot{r}\) and \(\dot{\theta}\) when the shell reaches an altitude \(y = 175 \text{ ft}\). Neglect aerodynamic drag. From the problem diagram, point \(O\) is at the origin, and point \(A\) is on the \(x\)-axis at \(x = 350 \text{ ft}\).)