close

標題:

ｍｅｃｈａｎｉｃｓ

 

此文章來自奇摩知識+如有不便請留言告知

發問:

A boy jumps up and his feet are 0.5m above the ground. (a)Find the hang-time of the boy. (b)Find the jumping speed of the boy. 點做？另外，題目內的ａ，ｕ，ｖ，ｓ，ｔ分別是什麼？

最佳解答:

In the question, take upward direction be positive. Acceleration, a = -10 ms-2 By v2 = u2 + 2as 0 = u2 + 2(-10)(0.5) Initial speed, u = 3.16 ms-1 Now, by v = u + at 0 = 3.16 - 10t t = 0.316 s So, the hang-time = 2t = 0.632 s b. The jumping speed = u = 3.16 ms-1 Inside the problem, acceleration, a = -10 ms-2 Initial speed, u = 3.16 ms-1 Final speed, v = -3.16 ms-1 displacement, s = 0 Hang-time, t = 0.632 s

其他解答:8758B59A7FA1EEA7

arrow
arrow
    文章標籤
    急救包 利息 影音 空格 股票
    全站熱搜
    創作者介紹
    創作者 dkdqgav 的頭像
    dkdqgav

    dkdqgav的部落格

    dkdqgav 發表在 痞客邦 留言(0) 人氣()

    E-mail轉寄