Understanding the Weakness of Gravity and its Role in the Universe

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Discussion Overview

The discussion revolves around the nature of gravity as a weak force and its role in holding celestial bodies such as planets, stars, and galaxies together. Participants explore the comparative strength of gravity relative to other fundamental forces and the implications of this weakness in the context of astrophysical structures.

Discussion Character

  • Exploratory
  • Technical explanation
  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • One participant questions how gravity, despite being a weak force, can hold planets, stars, and galaxies together, suggesting that gravity's attraction is counteracted in everyday life.
  • Another participant asserts that gravity is indeed weak compared to other fundamental forces, such as electromagnetism and nuclear forces, which are more effective at holding atoms together.
  • There is a repeated inquiry about whether gravity is the sole force responsible for holding stars and planets together, with some participants suggesting that the mass of these bodies contributes to the strength of the gravitational force.
  • One participant proposes that the cumulative effect of many weak forces can result in a strong resultant force, indicating a potential interplay of forces at work.
  • A later reply expresses satisfaction with the clarification provided, indicating a personal understanding of the topic.

Areas of Agreement / Disagreement

Participants express varying views on the role of gravity and its comparative strength, with some agreeing on its weakness while others question its sufficiency as the sole force responsible for holding celestial bodies together. The discussion remains unresolved regarding the interplay of forces involved.

Contextual Notes

Participants do not fully explore the implications of mass or the potential contributions of other forces, leaving some assumptions and dependencies on definitions unaddressed.

Samia qureshi
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If gravity is a weak force , then
How it holds planets , stars and galaxies together ?
let me know if i am right..?
Gravity only attracts there is no negative version of the force to push things apart and while gravity is powerful enough to hold galaxies together, it is so weak that you overcome it every day when pick up ball you are counteracting the force of gravity from all of earth.
 
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Answering the title: Yes.

It's weak in the context of the four fundamental forces: gravity, electromagnetism, "strong nuclear, weak nuclear", the last two of which are just forces which keep atoms together.

The key to understanding: Playing with magnets, you can easily see how electromagnetism can be stronger than gravity, while being 10000x smaller than the Earth. And of course, the nuclear forces are minuscule and of course resist gravity.

(Look up videos of MRI machines or neodymium magnets, then imagine how strong a magnet the size of the Earth would be)
 
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means only gravity is responsible for the holding of stars planets together ?
 
Samia qureshi said:
means only gravity is responsible for the holding of stars planets together ?
The sum of many weak forces = a strong resultant force!
 
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Samia qureshi said:
means only gravity is responsible for the holding of stars planets together ?

They have a lot of mass so the force is large enough to hold them together.
 
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Thank you now its clear to me :smile:
 

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