SOLUTION: The stopping distasnce d of a car after the brakes are applied varries directly as the square of the speed r. If a car traveling 80mph can stop in 360 feet, how many feet will it t

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Question 419922: The stopping distasnce d of a car after the brakes are applied varries directly as the square of the speed r. If a car traveling 80mph can stop in 360 feet, how many feet will it take the same car to stop wyhen it is traveling 30 mph?
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
The stopping distance d of a car after the brakes are applied varies directly as the square of the speed r.
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d = kr^2
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Solve for "k" using "a car traveling 80mph can stop in 360 feet"
360 = k*80^2
k = 0.05625
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How many feet will it take the same car to stop when it is traveling 30 mph?
d = 0.5625*30^2
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distance = 50.625 ft.
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Cheers,
Stan H.
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