So this one equals m1 g cosine alpha - and this one, the x component-- which is in the minus x direction now-- equals m1 g sine alpha.

得到m1gcosα,而x方向上-,这里是x负方向-,大小是m1gsinα

youdao

So this one equals m1 g cosine alpha - and this one, the x component-- which is in the minus x direction now-- equals m1 g sine alpha.

得到m1gcosα,而x方向上-,这里是x负方向-,大小是m1gsinα

youdao