What is the stopping distance of the car?

AI Thread Summary
The stopping distance of a car traveling at 12.0 m/s after noticing a red light involves two phases: the distance traveled before braking and the distance during braking. Initially, the car travels 6.12 meters in 0.51 seconds before the brakes are applied. After braking, using the equation vf^2 = vi^2 + 2ad, the calculated stopping distance is 11.6 meters. Adding both distances together, the total stopping distance from when the driver first sees the red light is approximately 17.72 meters. This calculation confirms the stopping distance based on the given parameters.
miamiheat5
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Suppose a car traveling at 12.0m/s sees a traffic light turn red. After 0.510s have elapsed, the driver applies the brakes, and the car decelerates at 6.20m/s^2. What is the stopping distance of the car, as measured from the point where the driver first notices the red light?


Homework Equations



d=vt
vf^2=vi^2+2ad



The Attempt at a Solution



d before breaking
d=vt
=12(0.51)
d=6.12m

d after breaking

vf^2=vi^2+2ad
0^2=12^2+2(-6.20)d
-144=2(-6.20)d
d=11.6m
 
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