Question

一个质量为m=1kg物体由光滑斜面顶端从静止开始下滑,25m,长2.5m,不计空气阻力.求：

Answer 1

mgh=mv2/2 m=1kg g=10m/s2 h=1.25m

v=5m/s

p=Fv=1kg×10m/s2×5m/s×1.25m/2.5m=25W