SOLUTION: The weight of an object varies inversely with the square of it's distance from the center of the earth. If an object 8000 miles from the center of the earth weighs 90 pounds, find

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Question 204388: The weight of an object varies inversely with the square of it's distance from the center of the earth. If an object 8000 miles from the center of the earth weighs 90 pounds, find it's weight when it is 12000 miles from the center of the earth.
Answer by Earlsdon(6294) About Me  (Show Source):
You can put this solution on YOUR website!
"The weight (W) of an object on earth varies inversely with the square of its (not it's) distance (d) from the center of the earth" This relationship can be expressed as:
W+=+k%2Fd%5E2 where k is the constant of variation.
To find the value of k, we'll substitute the given values of W = 90 lbs and d = 8000 miles.
90+=+k%2F%288000%29%5E2
k+=+90%2864000000%29
k+=+5760000000
So our formula becomes:
W+=+5760000000%2Fd%5E2 Substitute d = 12000 miles.
W+=+5760000000%2F%2812000%29%5E2
W+=+5760000000%2F144000000
highlight%28W+=+40%29lbs.