[題目] 彈簧與動能/位能的題目
[領域]
彈簧
[來源]
參考書
[題目]
A spring with spring constant k=200N/m is suspended vertically with
its upper ebd fixed to the ceiling and its lower end at position y=0.
A block of weight=20N is attached to the lower end, held still a moment,
and then released.
What are (a) the kinetic energy K,(b)the change(from the initial value)in
the gravitational potential energy ΔUg,and (c)the change in elastic potential
energyΔUe of the spring-block system when the block is at y=-5cm?
What are (d)K,(e)ΔUg,and (f)ΔUe when y=-10cm?
題目還有問-15cm和-20cm
[瓶頸]
題目有點看不懂
在掛物體的時候
事先讓它呈平衡的狀態嘛?
因為這個題目一直讓我聯想到簡諧運動
始終一直搞混
麻煩高手解答一下
另外
F=KX
20=200X
X不是等於0.1m嗎?
怎麼會有到-15和-20cm的時候呢?
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※ 編輯: ggyy940 來自: 210.64.163.155 (11/03 00:00)
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