Understanding the Weakness of Gravity and its Role in the Universe

In summary, gravity is a weak force in comparison to the other fundamental forces such as electromagnetism and the nuclear forces. However, it is the only force responsible for holding planets, stars, and galaxies together. This is because of their large masses, which result in a strong enough force to overcome the weakness of gravity.
  • #1
Samia qureshi
23
1
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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  • #2
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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  • #3
means only gravity is responsible for the holding of stars planets together ?
 
  • #4
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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  • #5
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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  • #6
Thank you now its clear to me :smile:
 

FAQ: Understanding the Weakness of Gravity and its Role in the Universe

What is the strength of gravity compared to other forces?

The strength of gravity is significantly weaker compared to other fundamental forces, such as electromagnetism and the strong and weak nuclear forces. It is approximately 10^38 times weaker than the strong force and 10^36 weaker than the weak force.

Why is gravity considered a weak force?

Gravity is considered a weak force because it has a relatively small impact on the behavior of particles and objects compared to other fundamental forces. This is due to its extremely small value of the gravitational constant and the fact that it only attracts, rather than repels, particles.

How does gravity affect large objects like planets and stars if it is a weak force?

While gravity may be considered a weak force at the particle level, it has a significant impact on larger objects like planets and stars due to the sheer mass involved. The force of gravity between two objects is directly proportional to their masses, so the larger the objects, the stronger the gravitational force between them.

Can gravity be manipulated or controlled?

At this time, there is no known way to manipulate or control the force of gravity. While it is possible to create small changes in the strength of gravity using extremely powerful gravitational fields, these changes are insignificant and cannot be used to manipulate or control the force itself.

Is there a theory that can fully explain gravity as a weak force?

While there are theories that attempt to explain gravity as a weak force, such as quantum gravity, there is currently no single theory that can fully explain it. The fundamental nature of gravity is still a topic of ongoing research and exploration in the scientific community.

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