Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Newtons law of universal gravitational question

  1. Oct 9, 2003 #1
    [​IMG]

    when doing this question, isnt the radius of the planet supposed to be added to the altitude of the satellite?
    having said that, would the term 'orbit' mean that the satellite is 35 000km away from the centre of mass, ie the centre of the planet and hence the radius is already included?

    thanks for any replies :smile:
     
  2. jcsd
  3. Oct 9, 2003 #2
    the distance d is the distance between the centres of mass of the two bodies. so yes, the radius of the planet should be added to the altitude of the satellite.

    i assume that in that sample question, 35,000km refers to the distance from the planet's centre of mass, otherwise the calculation would be innacurate. however, i would generally understand the orbit altitude to refer to the altitude above the surface of the planet.

    as long as you specify what you mean by certain terms, it doesn't really matter (the example you gave doesn't do this). this is physics, not semantics.
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?



Similar Discussions: Newtons law of universal gravitational question
Loading...