[問題] 一題物理 碰撞(已解答)
問一題有關碰撞的
http://i.imgur.com/plbylaV.jpg
![](https://i.imgur.com/plbylaV.jpg)
為什麼不能用
(M+m)gh=mgh' 求h'呢?
/*排球的位能+高爾夫球的位能
之後碰撞後能量都轉移給高爾夫球*/
##正解
排球的動能並不會完全轉移給高爾夫球
排球仍有位能
所以算式應該要改成
(M+m)gh=Mgh1+Mgh2
或者先求出它們到地面的V
用動量守恆(M+m)V=mV'
再用初速V'去算出最大高度呢?
##正解
此題目並不遵守動量守恆
地板有給排球作用力
造成兩顆球的速度方向改變
(一開始的總動量為正 而後來卻變負 怎麼算都不會動量守恆)
這兩個算法答案都不對QQ
可是我不知道原因
麻煩各位了謝謝~
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推
10/30 20:26, , 1F
10/30 20:26, 1F
不是呀 但我想知道為什麼那樣不行
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10/30 20:27, , 2F
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10/30 20:33, , 3F
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10/30 20:33, , 4F
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10/30 20:34, , 5F
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![](https://i.imgur.com/0BW2cNe.jpg)
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10/30 20:34, , 6F
10/30 20:34, 6F
謝謝QQ
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10/30 20:55, , 7F
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10/30 20:55, , 8F
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10/30 20:57, , 10F
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10/30 20:58, , 11F
10/30 20:58, 11F
不管是彈性還是非彈性碰撞 總動量都會受恆吧
※ 編輯: isbecky27 (111.248.90.230), 10/30/2016 21:10:15
※ 編輯: isbecky27 (111.248.90.230), 10/30/2016 21:12:33
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10/30 21:31, , 12F
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10/30 21:38, , 13F
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10/30 21:38, , 14F
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10/30 21:39, , 15F
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10/30 22:23, , 16F
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10/30 22:53, , 17F
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10/30 22:56, , 24F
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10/30 22:58, , 26F
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10/30 23:11, , 28F
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10/30 23:17, , 30F
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10/30 23:22, , 38F
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10/30 23:22, , 39F
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10/30 23:23, , 40F
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10/30 23:23, , 41F
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10/30 23:24, , 42F
10/30 23:24, 42F
噓
10/30 23:25, , 43F
10/30 23:25, 43F
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10/30 23:26, , 44F
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10/30 23:30, , 45F
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10/30 23:30, , 46F
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10/30 23:32, , 47F
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10/30 23:32, , 48F
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10/30 23:39, , 49F
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10/30 23:40, , 50F
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※ 編輯: isbecky27 (42.72.39.8), 10/31/2016 17:02:02
※ 編輯: isbecky27 (120.104.3.17), 10/31/2016 17:32:01
推
10/31 18:03, , 51F
10/31 18:03, 51F
謝謝各位的解答:)
※ 編輯: isbecky27 (120.104.3.17), 10/31/2016 20:36:20