Dealing with mass, acceleration and velocity

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SUMMARY

The discussion focuses on calculating the necessary thickness of barriers to safely stop a car traveling at 110 km/h, given that a person can withstand an acceleration of -0.030 m/s². The key formula identified for this problem is s = (1/2)at² + vt, where 's' represents distance, 'a' is acceleration, 'v' is initial speed, and 't' is time. The user seeks guidance on the appropriate formulas and problem classification, emphasizing the need for a constant deceleration assumption for the barrier.

PREREQUISITES
  • Understanding of kinematics, specifically the equations of motion.
  • Familiarity with the concepts of acceleration and deceleration.
  • Knowledge of unit conversions, particularly between km/h and m/s.
  • Basic grasp of physics principles related to force and mass.
NEXT STEPS
  • Research the derivation and application of the kinematic equation s = (1/2)at² + vt.
  • Learn how to convert speeds from kilometers per hour to meters per second.
  • Explore the concept of constant deceleration and its implications in real-world scenarios.
  • Investigate safety standards and engineering principles for barrier design in automotive safety.
USEFUL FOR

This discussion is beneficial for physics students, automotive safety engineers, and anyone involved in designing safety barriers or studying motion dynamics.

bree
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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,

[tex]s = \frac{1}{2}at^2 + vt[/tex]

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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