SOLUTION: The weight of an object on Earth varies according to the elevation of the object. In particular, the weight of an object follows this equation w=Cr^-2, where C is constant and r is

Algebra ->  Radicals -> SOLUTION: The weight of an object on Earth varies according to the elevation of the object. In particular, the weight of an object follows this equation w=Cr^-2, where C is constant and r is      Log On


   

Question 408751: The weight of an object on Earth varies according to the elevation of the object. In particular, the weight of an object follows this equation w=Cr^-2, where C is constant and r is the distance that the object is from the center of the earth.
Solve the equation w=Cr^-2 for r.
I am not sure where to start with this equation and no numbers to input the next problem states that sea level is 3,963 miles from center of the earth but I don't think I need to use that to solve for r in the first question. Please help!
Answer by richard1234(7193) About Me  (Show Source):
You can put this solution on YOUR website!
No, you only need to find r in terms of some constant C and the weight.

We have w+=+Cr%5E%28-2%29+=+C%2Fr%5E2. Multiplying both sides by r%5E2,

wr%5E2+=+C

r%5E2+=+C%2Fw

r+=+sqrt%28C%2Fw%29.