3 question運動力學 20分 - Ans.fyi 參考答案

question follwing

圖片參考：https://s.yimg.com/lo/api/res/1.2/snyVBf9bcKRhF1nQHLFarw--/YXBwaWQ9dHdhbnN3ZXJzO3E9ODU-/http://upload.lsforum.net/users/public/c295931u54.png

圖片參考：https://s.yimg.com/lo/api/res/1.2/xK51VK7LiFYf6tJzF0fVDg--/YXBwaWQ9dHdhbnN3ZXJzO3E9ODU-/http://upload.lsforum.net/users/public/f150862k54.png

c.
F=ma
F=0.14x (40/0.04)
F=140N
right?

d.
F=ma
a=F/m=Vf-Vi/change in time
F/0.14=-50-40/0.004
F=3150N
right?

e. How to do?

更新1:

question picture http://upload.lsforum.net/users/public/c295931u54.png http://upload.lsforum.net/users/public/f150862k54.png

回答 (1)

天同

2015-04-30 11:21 pm

✔ 最佳答案

(c) Correct.

(d) Correct.

(e) Your figures 3 and 4 are not shown. The answer below is given without referring to the figures.

A short contact time leads to less energy loss of the ball, and hence can provide a larger rebound speed.

👍 0 👎 0