1. Not finding help here? Sign up for a free 30min 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!

Shuttle moving in a circular orbit

  1. Mar 10, 2013 #1
    The space shuttle is moving in a circular orbit with a speed of 7.8km/s and a period of 87min. In order to return Earth, the shuttle fires its retro engines opposite to its direction of motion. The engine provide a deceleration of 6m/s^2 that is constant in magnitude and direction. What is the total acceleration of the shuttle?

    can't seem to understand how to start solving it. don't i need the radius of orbit?
     
  2. jcsd
  3. Mar 10, 2013 #2
    Yes. Use the universal law of gravitation to solve radius of the orbit.
     
  4. Mar 10, 2013 #3
    i tried to solve it but im not sure if it is correct.

    ω=2pi/T
    360/87x60=2/29
    V=ω.r
    2/29xr=7800
    r=113100m = 113,1km
    a = v^2/r = ω^2r (circular motion equations)
    (2/29)^2x113,1=78/145 km/sec^2 = 15600/29 m/sec^2

    the retro engine deceleration is 6m/sec^2
    15600/29-6=15426/29 m/sec^2

    is it correct? i really need help, confirmation on this.
     
  5. Mar 10, 2013 #4
    gravitation law requires masses if am not mistaken and also i think this is a circular motion question.
     
  6. Mar 10, 2013 #5
    Satellite mass will cancel out.
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?
Draft saved Draft deleted