反作用力(物理高人請進)

2008-09-27 9:47 pm
跟劇牛頓第三定律,當貨車撞上汽車的時候,貨車給汽車的力應該是等於汽車給貨車的力,
但係汽車卻嚴重受損,貨車則反之
其中一個因素係同佢地的材料和結構有關啦
如果排除呢D因素,應該仲有力學上的因素架,係咪同質量,慣性有關?如果係,點樣影響到佢地的受損程度?
請詳釋
更新1:

Mcar=1000kg Mtruck=100000kg Vcar=10m/s Vtruck= 0m/s

回答 (2)

2008-09-29 1:03 am
✔ 最佳答案
The main reason is that the mass of a car is much smaller than the mass of a truck, thus the car suffers a greater change of velocity during collision.

Since during an impact, the force and time duration acting on both the car and truck are the same, that is to say, they both suffer from the same 'impulse' (impulse = force x time)

But impulse = change of momentum = mass x change in velocity
Because the changes of momentum of the car and truck are the same, one with smaller mass (the car) will have a greater change in velocity than one with larger mass (the truck).

This sudden rapid change in velocity of the car not only gives severe impact to passesngers but also gives serious damage to the car because of inertia.
2008-09-27 10:50 pm
你已經講咗答案,不過你冇講兩部車既方向及速度。


收錄日期: 2021-04-29 17:26:51
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