对物体进行受力分析可得
f = u FN = u （mg - Fsin37°）= 8 N
a = F合/ m =(F cos 37° - f ) / m = 7.2 m/s^2
s = 1/2 a t^2 = 14.4 m
W F = Fcos 37° s = 1152 J
