[填空题]
Every few hundred yeaxdo8acaf4n/ -,wd b3: sqp:c5yfjts4 ao/r ;v rs most of the p -1 xhzv+q+mnclanets line up on the same side of the Sun. Calculate the total force on the Earth due to Venus, Jupiter, and Saturn, assuming all four plavh z++cqxn -1mnets are in a line (Fig. 5-38). The masses are $M_{\mathrm{V}}=0.815 M_{\mathrm{E}}, M_{\mathrm{J}}=318 M_{\mathrm{E}}, \quad M_{\mathrm{S}}=95.1 M_{\mathrm{E}}$ , and their mean distances from the Sun are 108,150,778 , and 1430 million km , respectively. What fraction of the Sun's force on the Earth is this? $F_{Earth-planets}$ = $\times 10^{17}$ ${F_{Earth-plantes}}$ \ ${F_{Earth-sun}}$= $\times 10^{-5}$
