撞擊力量有幾大？

👨🏻‍🏫 學術台其他 - 科學

2010-12-10 9:21 pm

最近龍翔道發生交通意外，
有一輛跑車以130公里行走，車輛重一千公斤，
理大有一個教授計算出撞擊力量大約有六噸。

請問有無主修physics的朋友知道是怎樣計算出來的？

更新1:

the acceleration due to gravity 應該是向下加速，而跑車是向前行駛，前者在物體產生的力向下，而後者在物體產生的力則向前，為什麼不同兩種的力可以互相等同？

更新2:

一開始運用 force x impact time = change of momentum, 但你怎樣計算出force的數值？

更新3:

一開頭你個 60000 N 的數值係點計出黎架？F=ma ?

回答 (2)

天同

2010-12-10 9:58 pm

✔ 最佳答案

The crucial point is the impact time. If using the given data, we could estimate the impact time.

Use the formula: force x impact time = change of momentum
Force = 6 ton-f = 6000 kgf = 60000 N (take g, the acceleration due to gravity, to be 10 m/s^2 for simplicity of calculation).

Change of momentum of the car
= 1000 x (130 x 1000/3600) N.s = 36,111 N.s

Hence, 60000 x impact time = 36111
impact time = 0.6 s

Therefore, if the car collided with an impact time around 0.6 s, an impact force of about 6 tonf would be expected.

👍 0 👎 0

Atheist

2010-12-11 3:40 am

因為6噸=1000公斤

👍 0 👎 0

收錄日期: 2021-04-29 17:39:40
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20101210000051KK00463

檢視 Wayback Machine 備份