SOLUTION: Looking for assistance in creating an equation to solve the following problem. The force needed to keep a car from skidding on a curve varies jointly as the weight of the car an

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Question 329320: Looking for assistance in creating an equation to solve the following problem.
The force needed to keep a car from skidding on a curve varies jointly as the weight of the car and the square of the car's speed, and inversely as the radius of the curve. If a force of 3600 pounds is needed to keep an 1800 pound car traveling at 20 mph from skidding on a curve of radius 600 feet what force would be required to keep the same car from skidding on a curve of radius 570 feet at 50 mph?
Answer by Earlsdon(6294) About Me  (Show Source):
You can put this solution on YOUR website!
Ok, here's the equation:
Let F = Force required to keep car from skidding.
Let W = Weight of car in lbs.
Let S = Speed of car in mph.
Let r = Radius of the curve in feet.
Let k = the constant of variation.
F+=+%28W%2A%28S%29%5E2%2Fr%29%2Ak First, find the value of k. Substitute the given values of: F = 3600 lbs, W = 1800 lbs, S = 20 mph, and r = 600 ft.
3600+=+%281800%2820%29%5E2%2F600%29%2Ak Evaluate.
3600+=+%28%281800%2A400%29%2F600%29%2Ak
3600+=+%281200%29%2Ak
k+=+3 Now thw equation becomes:
F+=+%28W%2A%28S%29%5E2%2Fr%29%2A3 Now substitute the problem values of: W = 1800 lbs, S = 50 mph, and r = 570 ft.
You can work this out.
I got F = 23,684.2 lbs.