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tobya93
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1. In a crash simulation, a car traveling at x m/s can stop at a distance d m with a maximum deceleration. If the car is traveling at 2x m/s:
A. Stopping time is doubled
B. Stopping distance is doubled
C. Stopping distance is quadrupled
D. Both A and C
Ok, so I thought this was a relatively easy question. However, I managed to butcher it. My problem is, I do not understand which equation to use. To find if the distance doubled or quadrupled I used the equation: d = ((Vi + V)/2) * t. Since the car will be stopping the V will be zero and you simply get d = (Vi/2) * t. If the velocity is doubled, distance is doubled. However, the book used the equation V^2 = Vi^2 + 2ad. Thereby getting, stopping distance quadrupled.
Also for time they used V = Vi + at.
Answer is D.
Once again, I am lost to know which equation to use. Since both seemed to work..
Thanks for your help!
A. Stopping time is doubled
B. Stopping distance is doubled
C. Stopping distance is quadrupled
D. Both A and C
Ok, so I thought this was a relatively easy question. However, I managed to butcher it. My problem is, I do not understand which equation to use. To find if the distance doubled or quadrupled I used the equation: d = ((Vi + V)/2) * t. Since the car will be stopping the V will be zero and you simply get d = (Vi/2) * t. If the velocity is doubled, distance is doubled. However, the book used the equation V^2 = Vi^2 + 2ad. Thereby getting, stopping distance quadrupled.
Also for time they used V = Vi + at.
Answer is D.
Once again, I am lost to know which equation to use. Since both seemed to work..
Thanks for your help!