Angular Momentum: Keeping Planets on their Orbit

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Discussion Overview

The discussion revolves around the factors that keep planets in their orbits, particularly focusing on the role of gravitational attraction and angular momentum. It explores concepts related to motion, speed, and the underlying principles of physics that govern orbital dynamics.

Discussion Character

  • Exploratory, Conceptual clarification, Debate/contested

Main Points Raised

  • One participant questions what keeps planets in their orbits, suggesting that gravitational attraction from the star should pull them in.
  • Another participant proposes that the planets maintain their orbits primarily due to their speed.
  • A different participant adds that the gravitational pull depends on the distance between the planets and the sun, as well as the radius of their orbits.
  • There is a query about the source of the planets' speed or motion.
  • One response attributes the planets' speed to the angular momentum of the original spinning cloud of gas and dust that formed the solar system.
  • Participants express curiosity about why the planets do not stop moving in their orbits.
  • Another participant attributes the continuous motion of planets to Newton's laws of motion.

Areas of Agreement / Disagreement

Participants express various viewpoints regarding the factors influencing planetary motion and the reasons for their sustained orbits. There is no consensus on the explanations provided, and multiple competing ideas remain present in the discussion.

Contextual Notes

The discussion does not resolve the complexities of gravitational forces, angular momentum, or the implications of Newton's laws as they relate to orbital mechanics.

mreq
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Hy.

What makes the planets to keep their position on the orbit (the same orbit). Shouldn't be attracted by the gravitation of the star ?

Thanks!
 
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Hi there,

To be very simple, their speed!
 
they keep in their orbits due to the force of attraction or gravitational pull which depends on the distance of the planets and the radius of the orbits from each other and the sun.
 
And what give them the speed (motion)?
 
mreq said:
And what give them the speed (motion)?
The angular momentum of the original spinning cloud of gas/dust that formed the solar system.
 
And why it doesn't stop ?
 
mreq said:
And why it doesn't stop ?

Newton's laws of motion.
 

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