- #1
physics(L)10
- 101
- 0
Homework Statement
How far above the Earth must an object be in order to lose 30% of its weight?
Homework Equations
ma=Gm(Mearth)/r^2
a=v^2/r
v=2pir/T
The Attempt at a Solution
I think the 30% lost weight would be the same as the Earth's weight losing 30%. Therefore, I can put Mearth=(0.30)(6x10^24)
We have to solve for r to find the radius and then subtract it from the radius of the Earth to find where this object is.
So rearranging the equation we get:
4pi^2r^3/T^2=0.30GMearth/r^2, where T=1 day and needs to be converted to seconds.
Finally, we rearrange to solve for r and get:
r=0.30GMearth/4pi^2