SOLUTION: 1. Many people know that the weight of an object varies on different planets, but did you know that the weight of an object on Earth also varies according to the elevation of the o

Algebra ->  Radicals -> SOLUTION: 1. Many people know that the weight of an object varies on different planets, but did you know that the weight of an object on Earth also varies according to the elevation of the o      Log On


   

Question 297226: 1. Many people know that the weight of an object varies on different planets, but did you know that the weight of an object on Earth also varies according to the elevation of the object? In particular, the weight of an object follows this equation: w=Cr^-2, where C is a constant, and r is the distance that the object is from the center of Earth.
b. Suppose that an object is 100 pounds when it is at sea level. Find the value of C that makes the equation true. (Sea level is 3,963 miles from the center of the Earth.)
I am confused about how do to the question.
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
Hint: At sea level, we're given that we are "3,963 miles from the center of the Earth". So this means that r=3963. Also, because we're are supposing that "an object is 100 pounds when it is at sea level", we can say that w=100. Plug these two values into w=Cr%5E%28-2%29 to get 100=C%283963%29%5E%28-2%29.