Derive equation of trajectory of a body around a fixed body attracted by gravity

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SUMMARY

The discussion revolves around deriving the equation of trajectory for a body of mass m projected around a fixed spherical body of mass M, using Newton's Law of Gravity. The trajectory can be classified as an ellipse, parabola, or hyperbola, depending on the initial conditions such as velocity and distance. The solution involves complex calculations using polar coordinates and integrals, specifically addressing the Kepler problem. Participants seek guidance on resources that detail the mathematical derivation of these trajectories.

PREREQUISITES
  • Newton's Law of Gravity
  • Understanding of conic sections (ellipse, parabola, hyperbola)
  • Familiarity with polar coordinates
  • Basic calculus, including integration techniques
NEXT STEPS
  • Study the derivation of the Kepler problem using Newton's Law of Gravity
  • Learn about the properties of conic sections in orbital mechanics
  • Explore integration techniques in polar coordinates
  • Review examples of trajectory calculations in celestial mechanics
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Students and educators in physics, astrophysics, and mathematics, particularly those focusing on orbital mechanics and gravitational interactions.

gupta.shantan
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Homework Statement



There is a fixed spherical body of mass M whose center is to be taken as origin. Another body of mass m whose initial position vector [itex]\vec{r}[/itex] is given. This body is projected with initial velocity [itex]\vec{v}[/itex]. Find the equation of trajectory of body with mass m around the body with mass M.

Homework Equations



Will the trajectory be an ellipse, just like the orbit of Earth around the sun?

The Attempt at a Solution



I tried solving the position using Newton's Law of Gravity. I also tried using the formula a = v dv/dx and integrating but was unable to reach a solution.

Any help is greatly appreciated...
 
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Your problem is known as Kepler problem.

It is possible to derive the trajectory with Newton's Law of gravity, but this is an ugly calculation, at least ~2 pages long, involving polar coordinates, some substitutions and messy integrals.

Depending on the velocity, the radius and the masses M and m, the trajectory can be:
- an ellipse
- a parabola
- a hyperpola
which are all conic sections
 
thank you mfb
but i am willing to go through the messy mathematics. So can u please help me by giving me a link to where this Kepler problem has been solved.
 

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