1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Homework Help: Grade 12 Physics Question

  1. Jan 25, 2012 #1
    Mars travels around the Sun in 1.68 Earth years in an approximately circular orbit with a radius of 2.18 x 10^8 km. Determine the mass of the Sun.

    Fairly easy, I know most of how to do it but I keep getting wrong answers. Help me out a bit? Thanks!
  2. jcsd
  3. Jan 25, 2012 #2
    Ok well you can you can set Fg equal to Fc.

    Fg = Fc

    G msmm/r2 = mm2r/T2

    Simplifies to

    G Ms = 4π2r3/T2


    (6.67x10-11) Ms = 4(3.14)2(2.18x1011)3/(52980480)2

    Ms = UDOIT kg
    Last edited: Jan 25, 2012
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook