A:仅限于一维碰撞
B:任何情况下m1v12+m2v22=m1v1′2+m2v2′2也一定成立
C:式中的v1、v2、v1′、v2′都是速度的大小
D:式中的不变量是m1和m2组成的系统的质量与速度乘积之和
Rice, please.
Hello! My name is Cutie. I'm a lovely ____. My hair is long and my eyes are____ . I like ____ and____. What ____ you?
He doesn't have much time ____ (listen) to music from Monday to Friday.