Dealing with mass, acceleration and velocity

AI Thread Summary
The discussion revolves around calculating the thickness of barriers needed to safely stop a car traveling at 110 km/h, given that a person can withstand an acceleration of -0.030 m/s². The participant seeks guidance on identifying the appropriate formulas and the nature of the problem, specifically whether it involves constant velocity, displacement, or friction. A key formula mentioned is s = 1/2 at² + vt, assuming constant deceleration from the barrier. The participant expresses gratitude for the assistance and plans to apply the suggested formula to solve the problem. The conversation highlights the importance of understanding acceleration and its impact on safety in automotive scenarios.
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Homework Statement


Problem: A person wearing a seatbelt can withstand an acceleration of -0.030 m/s2. How thick should barriers be to safely stop a car that hits a barrier at 110 km/h?


Homework Equations


F=m*a?


The Attempt at a Solution


I so far have no attempt. I do not know what sort of formula can be used or what type of problem it is ie. constant velocity, displacement, friction so on. The sort of help that I need is a possible formula you might know of or even what kind of problem this is.
 
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I think the key formula is, with a=acceleration, v=initial speed, t=time and s=distance,

s = \frac{1}{2}at^2 + vt

Assume the barrier applies a constant deceleration.
 
Thank you Mentz114. That is very helpful! I'll try the problem using that formula now. Thanks again!
 

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