一、引力势能图11.引力功与引力势能首先讨论万有引力做功的问题.如图1所示,一个质量为M的均匀球体(譬如星球)静止(即选择它为参考系),另有一个质量为m的质点,仅在相互之间的万有引力作用下,由离球心为r B的一点B移动到离球心为r A的另一点A,则引力对质点所做的功为W=∫A B F·dr=∫A B G Mm r2dr上式积分,得W=(-GMm r)-(-GMm r) First, the gravitational potential Figure 11. Gravitational and gravitational potential First, we discuss the work of gravitation, as shown in Figure 1, a mass of M uniform sphere (such as the planet) is still (that is, choose it as the reference frame), and another one quality Only the mutual gravitational attraction, from the center of a ball B as a point B to move away from the center of the ball A r A another point, then the gravitational work for the particle W = ∫ ∫ ABF · dr = ∫ ABG Mm r2dr The integral of the above equation, W = (- GMm r) - (- GMm r)