# Finding the orbital height of a satellite

1. Feb 2, 2010

### centripitacal

1. The problem statement, all variables and given/known data
I have to find the orbital height of a satellite with a specific g force (ie. the acceleration due to gravity). g=5.7(ms)2

2. Relevant equations

So far I have been using the equation g=Gm/(r+h)2 to find the acceleration due to gravity, where G= gravitational constant, m=mass of the Earth ,r=radius of the earth and h= the orbital height from the Earth

except now I am given a specific g force and have been asked to find the height.

3. The attempt at a solution

2. Feb 2, 2010

### rock.freak667

Not sure what is puzzling you.

g=GM/(r+h)2 and they give you g=5.7 m/s2

∴5.7=GM/(R+h)2

G,M and R are all known, cross multiply and then do some algebra to get 'h'.

3. Feb 2, 2010

### centripitacal

Cheers,
bit slow on the uptake today, but that was all I wanted to know.

4. Feb 3, 2010

### centripitacal

Back again, moving the equation around dosn't help because the h is inside the brackets, along with the Earth's radius (r+h). What am I missing?

5. Feb 3, 2010

### rock.freak667

When you reach (R+h)2=A, take the square root of both sides.