[題目] 一題普物 拉起鐵鍊
[領域]普物 (題目相關領域)
[來源]91交大電物考古題 (課本習題、考古題、參考書...)
[題目]A chain of length L is bunched up on a frictionless floor.
A constant force F is applied to pull the chain until it is
fully extended. What is the final velocity of the chain?
[瓶頸]不知道這題是指往上拉還是往旁邊拉?
如果是往旁邊拉的話
我列的式子是F=xρ*dv/dt + ρv*dx/dt
其中x是已經拉開的長度 ρ是密度
如果是往上拉的話
式子就要改成F-xρ=xρ*dv/dt + ρv*dx/dt
可是這個微分方程我就不會解了QQ
因為沒有解答不確定哪個對(或者都錯XD
想知道我的想法有沒有錯誤
如果都沒錯的話我再來研究解微分方程
感謝!!!!
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◆ From: 111.243.88.244
※ 編輯: burialberyl 來自: 111.243.88.244 (11/22 13:02)
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