Re: [微積] ODE應用題
※ 引述《elongation (Takashi Sorimachi)》之銘言：
: 題目出處：90 中央機械
: A 16–foot long chain weighting m pounds per foot hangs over a
: small pulley, which is 20 feet above the floor. Initially, the
: chain is held at rest with 7 feet on one side and 9 feet on the
: other side, as in Figure 1. How long after the chain is released,
: and with what velocity, will the chain leave the pulley? (25%)
: 題目問"離開pulley時"，以我的想法是鏈條成整條垂直時即"離開pulley時"，
: 請問題目沒給pulley的尺寸是否有瑕疵？還是有其他意想不到的解法？
7入 * g * (- 3.5) + 9入 * g * (-4.5)
= 16入 * g * -8 + (1/2) * 16 * 入 * v^2
=> 7 * (-3.5) + 9 * (-4.5) = 16 * (-8) + (8/g) v^2
=> 解v
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推
02/11 16:26,
8年前
, 1F
02/11 16:26, 1F
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