2. Block A of mass mA =2 kg is on block B of mass mB =5 kg. The lower block is on a frictionless surface while the coefficient of static friction μs =0.25 between the two blocks. If they are moving together at constant velocity, v=5 m/s, what is the frictional force between A and B?
詳解 (共 1 筆)
助人為本
詳解 #7413728
所以這題它說是等速
所以加速度為0
注意這裡靜摩擦力不一定等於靜摩擦係數*正向力
正確來說是小於等於
實際靜摩擦力大小要看相對運動趨勢
但地面是無摩擦
水平方向也沒有外力,需要摩擦力來提供
所以和速度無關
摩擦力為0