Homework Help: Math

Posted by ASD on Friday, September 17, 2010 at 10:02am.

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.
a.Solve the equation w=Cr^-2 for r. The answer I came up with is r^-2=w/C: is this correct?
And would you please help me with b?
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.)
Thank you!

Math - ASD, Friday, September 17, 2010 at 11:03am
Ok, I went back and tried again. The equation I found when solving for r is r=sqrt(C/w)
Is this correct?
Then in b I would plug in the 100 for w, and the 3,963 for r to find the constant, C, correct?
Math - PsyDAG, Friday, September 17, 2010 at 11:06am
a is correct.

C = w/r^-2

w = 100

r = 1/(3963)^2

Solve for C.
Math - ASD, Friday, September 17, 2010 at 11:29am
So would my equation be C=100/(3963)^2 ...I'm confused
Math - ASD, Friday, September 17, 2010 at 11:57am
Please let me know if I did this correct for b...
100=C/(3,963)^2
100=C/15,705,369
100*C=(C/15,705,369)*C
100C=15,705,369
100C/100=15,705,369/100
C=157,053.69

Answer this Question

Related Questions

alegebra - 1. Many people know that the weight of an object varies on different ...
people - 1. Many people know that the weight of an object varies on different ...
math - Studying for a final help. Many people know that the weight of an object ...
algebra - You may have to convert from feet to miles several times in this ...
ALGEBRA - 1. Many people know that the weight of an object varies on different ...
math - 1. Many people know that the weight of an object varies on different ...
Math - 1. Many people know that the weight of an object varies on different ...
Math - 1. Many people know that the weight of an object varies on different ...
Math - Hint: Pay attention to the units of measure. You may have to convert ...
math 117 - Can some help me with this appendix please. Thank you Pay attention ...

For Further Reading

First Name:
School Subject:
Answer: