일반물리학 1 — Potential Energy and Conservation of Energy: Problem 38

38 Figure 8-37 shows a plot of potential energy $U$ versus position $x$ of a $0.200 \text{ kg}$ particle that can travel only along an $x$ axis under the influence of a conservative force. The graph has these values: $U_A = 9.00 \text{ J}, U_C = 20.00 \text{ J}, \text{ and } U_D = 24.00 \text{ J}$. The particle is released at the point where $U$ forms a “potential hill” of “height” $U_B = 12.00 \text{ J}$, with kinetic energy $4.00 \text{ J}$. What is the speed of the particle at (a) $x = 3.5 \text{ m}$ and (b) $x = 6.5 \text{ m}$? What is the position of the turning point on (c) the right side and (d) the left side?