2*3.14*500*0.8/4=628
6280/628=10
M=W/F=2πR/L=(2πR/nP)*η
=6280/F=(2π*500/1*4)*80%
=>F=6280/(2π*500/1*4)*80%
=9.99493043=10N
111.一螺旋起重機之手柄長度為50cm,摩擦損失估計為20%,螺旋導程為4mm..-阿摩線上測驗