A ball is dropped from the top of a building 576 ft high.
With what velocity should a second ball be thrown straight downward 3s later so that the two balls hit the ground simultaneously?
Physics
2013-11-12 5:01 am
回答 (1)
2013-11-12 6:39 am
✔ 最佳答案
h = vt - (1/2)at²When the ball is drop from the top
v = 0
let a = -32 ft/s^2
576 = (1/2)(32)t²
t = 6 second
Now the second ball has to take 576 ft in 3 second
576 = v(3) -(1/2)(-32)(3)^2
v = 144 ft / s
為什麽還會用英制計 physics？
在英制中，重力加速度是 32 ft / s^2
收錄日期: 2021-04-27 20:35:25
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20131111000051KK00218