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Gravitation course work

  • Thread starter Tom1
  • Start date
24
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1. Homework Statement

A planet around a star has an orbit that is not exactly an ellipse. In addition to the dominant Fo [tex]\alpha[/tex] r^-2 term due to gravity from the central star, the planet seems to be responding to a slight additional force which has the form F1 [tex]\alpha[/tex] r^-[tex]\alpha[/tex] where [tex]\alpha[/tex] is some constant.


2. Homework Equations

Included in 1.

3. The Attempt at a Solution

Where do I begin?
 

Answers and Replies

Kurdt
Staff Emeritus
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I have no idea since I don't know what you're supposed to be doing.
 
24
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Sorry, part of this seems to have been cut off.

Assuming there is a slight background density of material with spherically symmetric density p1 falling off as p1 (alpha) r^-B

Find the value of B in terms of alpha
 
24
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Can anyone help me get started please? I don't understand this at all and it's due soon.
 
Dick
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Near as I can tell you want to assume there is a mass distribution with density rho(r)=p1*(r/r0)^(-B). Now you want to figure out the radial dependence of the force it generates. Compute total mass as a function of r, M(r). Use that to calculate the force.
 

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