Question

S=nh ;F=G/n ;η=(G·h)/(F·S)=(G·h)/[(G/n)·nh]=(G·h)/(G·h)=100%

Answer 1

(G·h)/(F·S)=(G·h)/[(G/n)·nh这步错了.

如果你说F会等于Gn,那么就忽略了动滑轮重和绳轮摩擦,否则,就应该是,(G·h)/(F·S)=(G·h)/F·nh=GFn.