Stopping Distance + Reaction Time Problem -> Physics beginner

AI Thread Summary
A car traveling at 80 km/h with a reaction time of 0.5 seconds and a deceleration of 8 m/s² has a total stopping distance of 41.97 meters. The initial speed converts to 22.22 m/s, leading to a distance of 11.11 meters traveled during the reaction time. After braking begins, it takes approximately 2.78 seconds to stop, covering an additional 30.86 meters. The calculations are confirmed as correct, and additional kinematic equations are suggested for more efficient problem-solving. This discussion highlights the application of basic physics concepts in determining stopping distances.
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Stopping Distance + Reaction Time Problem ---> Physics beginner

Homework Statement


A car is traveling at 80km/h, and brakes with a reaction time of .5 seconds. The car decelerates at 8m/s/s, determine the stopping distance of the car.


Homework Equations



- V1 = V0 + at
- D = V0t + 1/2at2

Where:
V1 = Final Speed
V0 = Initial Speed
A = Acceleration
T = Time
D = Distance

The Attempt at a Solution



Distance Traveled before Braking:
80km/h = 22.22m/s

0.5 * 22.22m/s = 11.11 m

Distance After Reaction:
V1 = V0 + at
0 = 22.22 - 8t
t = 2.7775 seconds

D = V0t + 1/2at2
D = 22.22 * 2.7775 - [(8 * 2.77752)/2]
D = 30.86m

Total Stopping Distance = 11.11m + 30.86m
= 41.97 m

Notes
I am only beginning to learn some basic concepts of physics in class, so I'm not entirely sure about the equations.

My teacher has provided no answer sheet to the question, and I am finding it hard to grasp the method of solving the question without a step by step example from a similar question.

I'd greatly appreciate it if anyone could let me know if I am right, or how to do it if I am wrong.

Thanks :D
 
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Thank you for the help and additional formulas !
Now I'll be able to do my other sums :D
 

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