19.一雙線螺紋之螺旋起重機,節距為5mm,作用臂長20cm,若摩擦損失為50%,則需施力若干方能舉起3140N之重物?
(A)50N
(B)63N
(C)75N
(D)200N。
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統計: A(210), B(28), C(38), D(31), E(0) #2240780
統計: A(210), B(28), C(38), D(31), E(0) #2240780
詳解 (共 2 筆)
#5105064
2拍R*0.5/2*0.5=62.8
3140/62.8=50
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#6045951
輸入力=輸出力
=>F*2拍R*損失率 = W*L
=>F*2拍20*0.5 = 3140
=>F*20拍 = 3140
=>F=50(N)
=>F*2拍20*0.5 = 3140
=>F*20拍 = 3140
=>F=50(N)
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