Kinenatics (NOT cst acceleration)

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The discussion revolves around solving a kinematics problem involving variable acceleration rather than constant acceleration. The scenario describes a driver traveling at 15.5 m/s who encounters a deer 51.2 m ahead, with a reaction time of 0.810 seconds and a maximum deceleration of 8.11 m/s². The key challenge is determining the stopping distance after accounting for the reaction time before braking begins. The initial assumption is that the acceleration is constant during braking, leading to confusion about how to approach the problem. Ultimately, the discussion highlights the importance of understanding kinematic equations in scenarios involving variable acceleration.
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[SOLVED] kinenatics (NOT cst acceleration)

I have no idea how to solve a problem that doesn't have constant acceleration. I'm guessing you have to set up an equation using the given values and solve for the variable..but I don't know.

This is the question anyhow:

You're driving down the highway late one night at 15.5 m/s when a deer steps onto the road 51.2 m in front of you. Your reaction time before stepping on the brakes is 0.810 s, and the maximum deceleration of your car is 8.11 m/s^2. How much distance is between you and the deer when you come to a stop?
 
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I would assume the acceleration is constant in this problem. I think that if you slam the breaks from the beginning, you should be applying the maximum acceleration for that interval. What else could "slamming" the breaks mean besides hitting them as hard as you can?
 
ya got it nevermind
 
Cool!:smile:
 
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