Physics

[LittleGrizzly]

Seems like the best place to put this,
I have a test coming up on circular motion and i would like one of you guys to check over my answers as i missed a few of the lessons we had on it so the teacher gave me a quick half hour run through of it, i think i mostly get it but i want to make sure im not messing anything easy up.
1. The planet venus can be assumed to orbit the sun in a circular orbit whose radius is 1.08 x 10 (11) m (in brackets is to the power of). The mass of the sun is 2.00 x 10 (30) kg
write down an expression for
(i) the gravitational force on venus
(ii) the centripetal force required to act on venus to enable it to travel in a circularorbit. Use the fact these two expressions represent the same force to calculate the angular velocity of venus in its orbit.
Use the angular velocity to determine
a) the linear velocity of venus and
b) the period of the orbit of venus.
express your answer to b) in days
and heres my answers...

1i) F = G (m1 x m2 / r (2) )
Force = Gravitation constant x mass of object 1 x mass of object 2 / distance between object centres

ii) F= m2 r w (2)
Force = mass of object 2 x radius x angular velocity (2)

m2 x r x w (2) = G x m1 x m2 / r (2)
m2 (mass of venus) cancels leaving

r x w (2) = G x m1 / r (2)
(1.08 x 10 (11) ) x w (2) = (6.67 x 10 (-11) ) x (2.00 x 10 (30) ) / (1.08 x 10 (11) )
(1.08 x 10 (11) ) x w (2) = 0.01143689986

w (2) = 1.05897221 x 10 (-13)
w = 3.25418532 x 10 (-7)

a) v = r x w
v = 1.08 x 10 (11) x 3.25418532 x 10 (-7)
v = 35145.20146 ms - 1

b) T = 2pi/w
Time = 2 x pi (3.14) / angular velocity

Time = 19298224.85 seconds
321637.0808 minutes
5360.918013 hours
223.3590839 days orbit for venus around the sun