How to Calculate Speed When an Object Hits Another?

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To calculate the speed at which an object hits another, the kinematic equation v^2 = u^2 + 2as can be used, where v is the final speed, u is the initial speed, a is the deceleration, and s is the distance. In this case, the car's initial speed is 110 km/h (converted to m/s), it decelerates at 6.5 m/s², and travels 25 m before hitting the wall. Additionally, to find the time taken until impact, the equation Δx = ut + (1/2)at² can be applied. By organizing known quantities and selecting the appropriate equations, both the impact speed and time can be calculated effectively. Understanding these kinematic principles is essential for solving such problems.
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How do you calculate the speed at which one objects hits another. I know the initial speed , the deceleration and the distance. Is there anything else I need to know.
The car was traveling at 110km/h it decelerates at 6.5 m/s and hits a wall 25m away . so what formula do I use to calculate the speed at which the car hits the wall? Could I in any way also calculate the amount of time it took until the car hit the wall?
 
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wangwang2626 said:
How do you calculate the speed at which one objects hits another. I know the initial speed , the deceleration and the distance. Is there anything else I need to know.
The car was traveling at 110km/h it decelerates at 6.5 m/s and hits a wall 25m away . so what formula do I use to calculate the speed at which the car hits the wall? Could I in any way also calculate the amount of time it took until the car hit the wall?

Are you familiar with ##v^2 = u^2 + 2as## for the first part?

In kinematic problems, it's often helpful to list all the relevant equations, then write down which quantities you know, and which you need to determine in two columns. Then pick the best equation(s) for your purpose.

After you follow my advice, you should be able to select the correct equation to do the second part as well.
 
wangwang2626 said:
How do you calculate the speed at which one objects hits another? I know the initial speed, the deceleration, and the distance. Is there anything else I need to know?
The car was traveling at 110 km/h it decelerates at 6.5 m/s2 and hits a wall 25 m away. So what formula do I use to calculate the speed at which the car hits the wall? Could I in any way also calculate the amount of time it took until the car hit the wall?
##2a\Delta{x} \approx v^2-v_0^2##
##\Delta{x} \approx v_0t+\frac{a}{2}t^2##
 
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