How can kinematics problems be solved with reaction time taken into account?

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To solve kinematics problems considering reaction time, it's essential to account for the time taken to react before braking begins. In the example, a driver traveling at 25 m/s takes 1.0 second to react and then decelerates at 3.0 m/s². The total stopping time, including reaction time, is calculated to be 9.3 seconds. The appropriate kinematic equation can then be used to determine the distance from the bridge when the driver first noticed the sign. This approach emphasizes the importance of integrating reaction time into kinematic calculations for accurate results.
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Homework Statement


1) A driver is traveling at 25m/s when she spots a sign that reads "Bridge Out Ahead". It takes her 1.0 s to react and begin breaking. The car slows down at a rate of 3.0 m/s2. Luckily, she stops 5.0m short of the washed-out bridge.
(a) How much time was required to stop the car when she spotted the sign?
(b) How far was the driver from the bridge when she first noticed the sign(keep in mind her reaction time)

Homework Equations



The Attempt at a Solution


25 m/s / 3m/s2 = 8.3seconds + 1 second (reaction time) = 9.3 seconds.
b)
 
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For (b) there is one of the four kinematics that is particularly useful for this problem and many others being that you are given an initial velocity, an acceleration, a final distance, and you just found the time coordinate from completing (a). Which of the kinematics incorporates these all of these variables as well as pertaining to a displacement? That ought to get you in the right direction.

Joe
 
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