Question

急啊，求解物理题目,如下(一个很重要的assignment，78分的啊。。。)

Answer 1

The Radius of the moon is R1=1E6 km
The Radius of the planet is R2=5E6 km
The Mass of Planet is M2=8.94E24 kg (you may left the unit)
The Distance of the planet's surface is D=421600 km
The Velocity of the moon orbiting the planet is V=1734m/s
The mass of spaceship is m=1000 kg
The velocity of spaceship at 10000 m of the moon is u=400m/s
The landing velosity is v=0.5m/s
The gravity constant is G
Assume that the Mass of the moon is M1
V^2/(R1+R2+D)M1=GM1M2/(R1+R2+D)^2

The gravity acceleration of the planet is g
mg=GM2m/R2^2
g=GM2/R2^2

analyse the Force to the spaceship
ma=F-mg

the hight of the spaceship is h=10000m
u^2-v^2=2ah

Get F=m[(u^2-v^2)/2h+V^2(R1+R2+D)/R2^2]
=8766N