# Homework Help: Law of mass attraction

1. Jun 18, 2005

### bigman8424

anyone wanna check my work, i would greatly appriciate it:

the quest. asks you to find law of mass attraction to calculate force of gravational of jupiter towards sun:
used formula:

F = GMm/R2 = (6.67e-11)(1.99e30)(1.90e27)/(7.78e6)2
FJupiter = 4.17e33 Newtons ??

Then it asks centripetal force towards sun using law of dynamics??

2. Jun 18, 2005

### dextercioby

Gravity attraction force IS a centripetal force.

You may wanna check the distance (in "m") (actually the average between the major & the minor semiaxis) between the 2 celestial bodies.

Daniel.

3. Jun 19, 2005

### Chris Danger

this may suggest having to use $a_{n} = \frac{v^2}{r}$ to get acceleration, but you would need the velocity and the mass (to get the force from $F = ma$)