Motion問題 (物理)

2012-03-05 10:17 pm
Calculate the uniform acceleration of a sports car which starts from rest and travels a distance of 22m during the sixth second of its motion.

請把過程列出

Equations of Motion:
1. Vf = Vi+at
2. d = Vit+0.5at^2
3.Vf^2 = Vi^2+2ad
4.d = [(Vf+Vi)/2]t

Vf = final velocity
Vi = initial velocity
d = displacement
a = acceleration
t = time

回答 (3)

2012-03-06 12:21 am
✔ 最佳答案
Firstly, calculate the distance travelled at the first 5 seconds :
t = 5 s, vi = 0, a = ?, d = ?
d = vit + 0.5at²
d = 0 + 0.5a(5)²
d = 12.5a m
Distance travelled at the first 5 second = 12.5a m

Secondly, calculate the distance travelled at the first 6 seconds :
t = 6 s, vi = 0, a = ?, d = ?
d = vit + 0.5at²
d = 0 + 0.5a(6)²
d = 18a m
Distance travelled at the first 6 second = 18a m

Distance travelled between the 5th and 6th seconds = Distance travelled duringthe 6th second
18a - 12.5a = 22
5.5a = 22
a = 4 m/s²
acceleration of the sports car = 4m/s²
參考: fooks
2014-06-26 8:34 am
你厭倦往返補習班浪費的時間和體力嗎
你想在家裡躺在沙發,就可以上課嗎?
網路課程橫跨升學考試、教職考試、公職考試、執照考試、就業考試、語言進修等6大類50餘科,

超過500多門課程,為各界人士提供優質的線上教育服務。

自100年6月成立以來,使用會員在一年內就已突破3萬名,並培育出許多優秀的學員,

學員踴躍分享行動補習帶來的便利與效果,累積許多佳績見證。

免費試讀網址:
http://ad.mobchannels.com/redirect.phpk=b2d8a7d711229b382ee03f334d1eb477&uid=
2012-03-05 10:46 pm
Motion問題 (物理)Calculate the uniform acceleration of a sports car which starts from rest and travels a distance of 22m during the sixth second of its motion.
請把過程列出
Equations of Motion:

1. Vf = Vi+at => Vf=0+6a=6*11/9=22/3 mps

2. d = Vit+0.5at^2 => 22=0+0.5*36a

Thus a=44/36=11/9 mps^2

3.Vf^2 = Vi^2+2ad => (22/3)^2=2*11/9*22

4.d = [(Vf+Vi)/2]t => 22=22/3*0.5*6

Vf = final velocity
Vi = initial velocity
d = displacement
a = acceleration
t = time
2012-03-05 14:18:28 補充 我算的答案大多是Vf=3.7m/s
可是正確答案是4ms/s.....可能有誤
到底怎麼算??


收錄日期: 2021-04-13 18:34:07
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20120305000015KK03364

檢視 Wayback Machine 備份