Find centripetal acceleration with two masses and radius.

[2much]

Homework Statement

We are given the mass of the sun, ms = 1.99 x 10^30 and the mass of the venus, mv = 4.83 x 10^24. The distance from each other radius is r = 1.08 x 10^8.

What is the centripetal acceleration?

mv = 4.83 x 10^24 kg
ms = 1.99 x 10^30 kg
r = 1.08 x 10^8 km
G= 6 67x10^-11 N m2 /kg2

Homework Equations

Force of gravitational attraction
Fg = G mv ms / r^2

Centripetal Acceleration
ac = mv v^2 / r

The Attempt at a Solution

Since gravity causes the centripetal acceleration:
Fg = mv ac
G mv ms / r^2 = mv v^2 / r

Solving for v we get
v =$$\sqrt{} ms G / r$$

I am not getting the right answer, what is wrong with using these equations?

 

[spikethekitty]

Since gravity causes the centripetal acceleration:
Fg = ac
G mv ms / r^2 = mv v^2 / r

Force does not equal acceleration. F=ma. See if that fixes the problem.

 

[2much]

Force does not equal acceleration. F=ma. See if that fixes the problem.

I did have mv in the final equation, just forgot to mention it there. Still didn't give me the answer of 1.3x10^-2 m/s2

 

[tiny-tim]

hi 2much!

(try using the X² tag just above the Reply box )

Solving for v we get …

why are you finding v ?