Hi everyone
here are the correct formulas from yesterday's class:


Escape Velocity/speed:
1.
Kinetic energy = Potential energy
Notation form: Ek = Ep

1/2mv² = Gm₁m₂

V=√2Gm/r
2. Determining g of a planet:

Fg=mg Fg=Gm₁m₂/r²

g=Gm/r²

3. Determining r, m, T:

Fc=m4π²r/T² Fg=Gm₁m₂/r²

4π²r/T²=Gm₂/r²
solve for m:
m= 4π²r³/GT²

solve for T: T²= 4π²r³/Gm

* period and radius is all you need to use this formula

4. Orbital Velocity:Fc=mv²/r Fg= Gm₁m₂/r²
v²=Gm₂/r

** also remember that force formulas have r² (squared)but energy formulas have only r radius.

April 30, 2010 12:02 AM