[問題] 物理題目

[dahuanews (大話新聞)]

A 5.0kg box slides down a 5.0-m-high frictionless hill,

starting from rest,across a 2.0-m-wide horizontal surface,

then hits a horizontal spring with spring 500 N/m .

The other end of the spring is anchored against a wall.

The ground under the spring is frictionless,

but the 2.0-m-wide horizontal surface is rough.The coefficient

of kinetic friction of the box on this surface is 0.25


a. what is the speed of the box just before hitting the spring

b. 此 box 能造成 spring 壓縮多長?

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A flock of ducks is trying to migrate south for the winter,

but they  keep being blown off course by wind blowing from the west at

6.0m/s .A wise elder duck finally realize that the solution is to

fly at an angle to the wind .If the duck can fly at 8.0m/s relative

to the air,what direction should they head in order to move directly south?


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噓 nightkid:看過你前面幾篇文章 我決定這篇開始給你2
→ dahuanews:因為你不會只能空按2?
噓 nightkid:我會 但是我討厭幫別人寫作業
→ LoveMR2:高中板都不高中板了
→ LoveMR2:去物理板問  有很難嗎？
→ nightkid:連個自己的想法都沒有 把題目丟出來 連翻譯都懶
→ nightkid:擺明就是坐享其成
噓 qoo60606:高中出英文題喔 我好怕
噓 ttpshb03:......
噓 arthur810827:英文老師常請假
噓 gj942l41l4:我英文不好