Question 464009
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 travelling 30 mph can stop in 50 ft"
50 = k*30^2
k = 50/900
k = 0.0556
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Equation:
d = 0.0556*r^2
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How many feet will it take the same car to stop when it is travelling 20 mph?
d = 0.0556*20^2
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distance = 22.22 ft
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Cheers,
Stan H.
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