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: Plotting tidal force vectors on the surface of the earth

  1. Apr 27, 2013 #1
    How can I plot the tidal force vectors on the surface the Earth in Mathematica or Python?

    The potential energy of the tidal force on the poles are
    U = -GM_{moon}m_{water}\left(\frac{1}{d}+\frac{x}{d_0^2}\right)
    where ##d_0## is the distance between the moon and the earth 384400 km.

    The equation of motion for forces acting on mass m is
    m\ddot{\mathbf{r}} = m\mathbf{g} + \mathbf{F}_{NG} - GM_{moon}m_{water}\left(\frac{\hat{\mathbf{d}}}{d^2} - \frac{\hat{\mathbf{d}}_0}{d_0^2}\right)

    Force ng is the non gravitational forces.

    I am not sure what I need to use to plot the vector lines coming from the Earth due to the moon.

    I know the tidal forces bulges out on the horizontal ends and pushes in on the poles.
  2. jcsd
  3. Apr 27, 2013 #2


    Staff: Mentor

    this might help for plotting on a sphere using matlab:


    You just have to modify the code for what you want. There may be another addition that will draw an earth profile on the sphere but I couldn't find it.
  4. Apr 28, 2013 #3
  5. Apr 28, 2013 #4


    Staff: Mentor

Share this great discussion with others via Reddit, Google+, Twitter, or Facebook

Have something to add?
Draft saved Draft deleted