一道关于角动量的题
问题描述：
一道关于角动量的题
A uniform,spherical planet of mass M and radius R moves SLOWLY with an essentially uniform speed v through a cloud of interstellar dust particles,whose density is ρ.The dust particles are attracted towards the planet,and some of them would eventually fall onto its surface.Find the resulting retarding force on the planet due to the dust cloud
一定要用到角动量，希望大家再努力想想
是ucla的入学考试题，我小妹在美国，老师只提示要用角动量，其他没说。我知道的就这么多。
答
angular momentum...who is rotating?I think what I did was right.refer to 3,angular momentum is a MAYBE,not a must.I used momentum,which is in the list as well.Firstly,energy is NOT conserved,because t...