問題詳情
22.若僅施力50kg，欲將250kg的重物利用斜面推上貨車，已知貨車高度為1.25公尺，若不計算摩擦，則斜面需多長？
(A)6.
(B)5.
(C)4.
(D)3.75。 .
(A)6.
(B)5.
(C)4.
(D)3.75。 .
參考答案
無參考答案
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