# Universal gravitation

1. Mar 1, 2008

### ookt2c

1. The problem statement, all variables and given/known data
A synchronous satellite, which always remains above the same point on a planet's wquator, is put in orbit around jupiter to study the famous red spot. jupiter rotates once every 9.84 h. find the altitude of the satelite

2. Relevant equations

jupiter: mass in kg 1.90E27,Mean radius 6.99E7,period of revolutions3.74E8,Mean distance from the sun7.78E11 (t^2/R^3)(S^2/M^3)= 2.97E-19

3. The attempt at a solution

I dont know where to start , missed a day of class

2. Mar 1, 2008

### Shooting Star

The force of gravity must be equal to the centripetal force. (But this is true for even if the satellite is not synchronous.)

3. Mar 1, 2008

### kdv

Strictly speaking, this is possible only if the point on th eplanet is at the equator. I don't think that the Red Spot is on th eequator but let's pretend it is.

Then you have to impose that the force of gravity on the satellite is equal to m tiomes the radial acceleration so
$$F_{grav} = m \frac{v^2}{r}$$

where "r" is the distance from the satellite to the center of the planet.