[題目] 動力學彈性碰撞
[領域] 應用力學 ─ 動力學
[來源] Vector Mechanics for Engineers 9th
[題目] A 70-g ball B dropped from a height h=1.5m reaches a height h"=0.25m
after bouncing twice from identical 210-g plates. Plate A rests directly on
hard ground, while plate C rests on a foam-rubber mat. Deterine
(a) the coefficient of restitution between the ball and the plates,
(b) the height h' of the ball's first bounce.
●→
↑
○
↑
h=1.5m
h' ○
h"=0.25m
↓ _____↓_____ __________ (plastic)
(plastic) ============== (rubber mat)
[瓶頸] 先解說圖，最左邊是球放在高度為1.5m的初始靜止狀態，從靜止往右邊墜落
(Vx多少不重要...)，可以看成這顆球往右彈跳，第一次彈跳跳在彈性系數為e的
plastic板，第二次彈跳跳在放在foam-rubber mat(查翻譯得知單字為泡沫橡膠墊，
e應該是0?)上的plastic，並且彈跳高度h"為0.25m，在此我不知rubber mat用途為何
這題應該是問 (a) plastic的彈性系數e (b)第一次彈跳高度h'
因為網路上這本課本解答還沒出來(只到8th)，外加看前面找不到解法，只知道答案為
e=0.923 h'=1.278m
不知該如何算出這個難題
提示：
碰撞公式： e( v1 - v2 ) = v2' - v1'
線性守恆： m1v1 + m2v2 = m1v1' + m2v2'
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