作业帮美国大学物理题 求救命啊Problem 7.The figure below is a graph of the energy of a system of a planet interacting with a star.The gravitational potential energy Ug is shown as the thick curve,and plotted along the vertical axis are various va
来源：学生作业帮助网 编辑：作业帮 时间：2024/11/26 09:37:37
美国大学物理题 求救命啊Problem 7.The figure below is a graph of the energy of a system of a planet interacting with a star.The gravitational potential energy Ug is shown as the thick curve,and plotted along the vertical axis are various va
美国大学物理题 求救命啊
Problem 7.The figure below is a graph of the energy of a system of a planet interacting with a star.The gravitational potential energy Ug is shown as the thick curve,and plotted along the vertical axis are various values of K+Ug.Suppose that K+Ug of the system is A.Find all of the true statements below.
1.The potential energy of the system decreases as the planet moves from r1 to r2.2.The potential energy of the system increases as the planet moves from r1 to r2.
3.When the separation between the two bodies is r2,the kinetic energy of the system is A-‐B.
4.The system is a bound system; the planet can never escape.5.The path traced by this orbiting system is a circle.
6.When the separation between the two bodies is r1,the kinetic energy of the system is B-‐C.
A) 2,3,4
B) 1,3,4
C) 2,4,5
D) 1,4,5
E) 2,4,6
美国大学物理题 求救命啊Problem 7.The figure below is a graph of the energy of a system of a planet interacting with a star.The gravitational potential energy Ug is shown as the thick curve,and plotted along the vertical axis are various va
A
1) 错,r1到r2过程中,纵坐标增高,说明总能量加大.
2) 对
3) 对,总机械能为A,所以当行星处于r2时,动能为总机械能A-B处的势能
4)对,这条曲线过了A点还在增高,说明行星往更高的轨道运行需要更多的能量,因而是为边界的,不能逃逸
5)错,半径可以变,不一定是个圆
6)错,参考3,应该为A-C