Re: [問題] 動能的來源
※ 引述《calros (【宇】)》之銘言：
: K=1/2mv^2 ＆ U=mgh
: 請問能告訴我 這2個公式的推演過程嗎
: 感謝各位高手!!
這是我以前打的
基本這兩個是從功推導出來的
K的過程是這樣
→
→ → → → dｖ → → dｒ
W = ∫Ｆ．dｒ = ∫mａ．dｒ = m∫-----．dｒ = m∫dｖ．-----
d t d t
→ → 1 → → 1 → → → →
= m∫dｖ．ｖ = ---m∫2dｖ．ｖ = ---m∫(dｖ．ｖ+ｖ．dｖ)
2 2
1 → → 1 v2 2 1 2 1 2
= ---m∫d(ｖ．ｖ) = ---m∫ dv = ---mv2 - ---mv1 = ΔK
2 2 v1 2 2
U的話是計算保守場內移動所做的功
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Deserves death! I daresay he does. Many that live deserve death. And some die
that deserve life. Can you give that to them? Then be not too eager to deal out
death in the name of justice, fearing for your own safty. Even the wise cannot
see all ends.
Gandalf to Frodo
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◆ From: 140.120.25.235
※ 編輯: Gwaewluin 來自: 140.120.25.235 (08/20 15:19)
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