Question

一个质量为1kg的物体在一个10N的水平拉力作用下沿水平面由静止开始运动,前进2m后突然撤去拉力.再前进1m时物体仍在运

Answer 1

F-f=ma , a=5/1 = 5 ,

vv - v0v0 = 2as , v = 2*根号5 .

滑行：

a' = f/m = -5

v'v' - vv = 2a's' , v'v' -20 = -10, v' = 根号10

0 - vv = 2a's'‘ s’‘ = 2

S = s+s’‘ = 4米