The Naked Scientists

The Naked Scientists Forum

Author Topic: Discussion against gravity  (Read 19638 times)

Offline syedbukhari39

  • Jr. Member
  • **
  • Posts: 24
    • View Profile
Discussion against gravity
« on: 15/11/2010 08:50:50 »
Do any one can prove the existence of force of gravity?
How can you describe the effectiveness of gravity in the universe?
I think there is no gravity in this world
Please comment and guide me if i am wrong


 

Offline Soul Surfer

  • Neilep Level Member
  • ******
  • Posts: 3345
  • keep banging the rocks together
    • View Profile
    • ian kimber's web workspace
Discussion against gravity
« Reply #1 on: 15/11/2010 08:57:43 »
You are wrong!  Please explain as clearly and fully a possible why you consider that the rest of science is wrong about this and then we may be able to help you.
 

Offline syedbukhari39

  • Jr. Member
  • **
  • Posts: 24
    • View Profile
Discussion against gravity
« Reply #2 on: 15/11/2010 09:11:20 »
if the gravity exists then it should attract the objects (heavy and light) at the same rate but the lighter objects do not appear to admit this force like dust,smoke etc
 

Offline JP

  • Neilep Level Member
  • ******
  • Posts: 3366
  • Thanked: 2 times
    • View Profile
Discussion against gravity
« Reply #3 on: 15/11/2010 09:16:47 »
Lighter objects don't seem to fall because they're so tiny that the air molecules bouncing around is enough to keep them floating.  Heavier objects are much bigger than the air molecules and so they are unaffected by them.

If you dropped some dust and a bowling ball in a vacuum, where there is no air, they'd take the same amount of time to reach the ground.
« Last Edit: 15/11/2010 09:21:21 by JP »
 

Offline JP

  • Neilep Level Member
  • ******
  • Posts: 3366
  • Thanked: 2 times
    • View Profile
Discussion against gravity
« Reply #4 on: 15/11/2010 09:20:37 »
Here's a youtube of the Mythbusters testing this concept.  They use a feather (which is very light and effected by air) and a hammer:
feature=related

In a vacuum they fall at the same rate.
 

Offline syedbukhari39

  • Jr. Member
  • **
  • Posts: 24
    • View Profile
Discussion against gravity
« Reply #5 on: 15/11/2010 09:32:15 »
I 100 % agree with you in vacuum they fall at the same rate
what causes the difference in the behavior of object
Air causes the difference
Actually gravity is dependent of air and the actual force is air not the gravity
 

Offline JP

  • Neilep Level Member
  • ******
  • Posts: 3366
  • Thanked: 2 times
    • View Profile
Discussion against gravity
« Reply #6 on: 15/11/2010 09:42:38 »
If the force was caused by air, all things would fall in exactly the same way in a vacuum.  This isn't true, since things on the moon in a vacuum fall more slowly than things on the earth in a vacuum.

The only consistent answer is that there's a force that depends on mass and another force that depends on air.  The mass-dependent force is gravity.  The air-dependent force is air resistance.
 

Offline syedbukhari39

  • Jr. Member
  • **
  • Posts: 24
    • View Profile
Discussion against gravity
« Reply #7 on: 15/11/2010 10:06:02 »
As you said that the air is playing the role of resistive force then in vacuum gravitational force should be more effective 
 

Offline QuantumClue

  • Hero Member
  • *****
  • Posts: 613
    • View Profile
Discussion against gravity
« Reply #8 on: 15/11/2010 10:34:37 »
If you are asking why gravity does  not overcome air, it does. The object eventually reaches ground zero. Air resistence only prelongs the fall.
 

Offline syedbukhari39

  • Jr. Member
  • **
  • Posts: 24
    • View Profile
Discussion against gravity
« Reply #9 on: 15/11/2010 10:44:16 »
NO As JP said that Lighter objects don't seem to fall because they're so tiny that the air molecules bouncing around is enough to keep them floating.
Then if we assume that there is no air just like in vacuum then the tiny particles should come down if the gravity exists
 

Offline JP

  • Neilep Level Member
  • ******
  • Posts: 3366
  • Thanked: 2 times
    • View Profile
Discussion against gravity
« Reply #10 on: 15/11/2010 10:54:39 »
As you said that the air is playing the role of resistive force then in vacuum gravitational force should be more effective 

No.  Gravitational force only depends on mass.  It's completely independent of what air is there.

Total force is the sum of gravitational force and air resistance (and any other forces that might be there).  It is total force that determines how the object behaves. 
 

Offline syedbukhari39

  • Jr. Member
  • **
  • Posts: 24
    • View Profile
Discussion against gravity
« Reply #11 on: 15/11/2010 11:09:14 »
I am still confused
if the gravitational force only depends on mass and independent of air then why do a massive objects fall down more rapidly in presence of air then much slower in vacuum although the there is no resistive medium in vacuum.
 

Offline JP

  • Neilep Level Member
  • ******
  • Posts: 3366
  • Thanked: 2 times
    • View Profile
Discussion against gravity
« Reply #12 on: 15/11/2010 11:12:47 »
I am still confused
if the gravitational force only depends on mass and independent of air then why do a massive objects fall down more rapidly in presence of air then much slower in vacuum although the there is no resistive medium in vacuum.

Can you give an example?
 

Offline syedbukhari39

  • Jr. Member
  • **
  • Posts: 24
    • View Profile
Discussion against gravity
« Reply #13 on: 15/11/2010 11:25:49 »
As you said that gravitational force depends only on mass and air is performing the role of resistive force then if we remove the air from the system then falling object should take much more less time to reach on the surface because there is no resistive force at the moment, gravitational force should attract the falling object more rapidly.
 if we throw  an object from the top of the building it will cover the distance to reach on the surface of the earth very quickly on the other hand if we throw that stone in a system where there is no air, it will take more time to reach on the surface although the gravity is constant for both the system then why there is a difference in behavior of falling object.   
 

Offline QuantumClue

  • Hero Member
  • *****
  • Posts: 613
    • View Profile
Discussion against gravity
« Reply #14 on: 15/11/2010 11:34:07 »
NO As JP said that Lighter objects don't seem to fall because they're so tiny that the air molecules bouncing around is enough to keep them floating.
Then if we assume that there is no air just like in vacuum then the tiny particles should come down if the gravity exists
If you take into consideration gravity is very weak, then of course if you apply enough resistence it can overcome the power of gravity. To understand the magnitude of gravity, just place a paper clip and take a very small magnet. Place the paper clip on the ground and see if the magnet will attract it... That tiny magnet is overcoming the power of the entire earth!

And where are particles coming down in the vacuum? I am confused by this.
 

Offline syedbukhari39

  • Jr. Member
  • **
  • Posts: 24
    • View Profile
Discussion against gravity
« Reply #15 on: 15/11/2010 12:20:01 »
 If you take into consideration gravity is very weak, then of course if you apply enough resistence it can overcome the power of gravity. To understand the magnitude of gravity, just place a paper clip and take a very small magnet. Place the paper clip on the ground and see if the magnet will attract it... That tiny magnet is overcoming the power of the entire earth

As you admitted that the gravity is very weak force, a magnet can overcome on this force.On one side it is strong enough that whole the universe is controlled and governed by this gravitational force and on the other hand it is so weak that a small magnet can overcome on it. How it is possible?
the magnitude of force is same but the results are different for different conditions.
Actually my point of view is that there is no gravity in this world because it fails to explain many things
 

Offline QuantumClue

  • Hero Member
  • *****
  • Posts: 613
    • View Profile
Discussion against gravity
« Reply #16 on: 15/11/2010 12:47:47 »
Celestial objects don't have the gravitational pull they would on objects on earth - there are signs of gravitational influences of our nearest celestial body, the moon, however, planets, star systems ect are all subject to the inverse square law, meaning gravity's grip weakens over large distances, so your theoretical application is invalid.
 

Offline JP

  • Neilep Level Member
  • ******
  • Posts: 3366
  • Thanked: 2 times
    • View Profile
Discussion against gravity
« Reply #17 on: 15/11/2010 13:19:59 »
Actually my point of view is that there is no gravity in this world because it fails to explain many things

Clearly, there is gravity.  It doesn't explain everything, but that doesn't mean it doesn't exist.
 

Offline Bill S

  • Neilep Level Member
  • ******
  • Posts: 1818
  • Thanked: 11 times
    • View Profile
Discussion against gravity
« Reply #18 on: 15/11/2010 15:35:26 »
syedbukhari39, here's a suggestion. Read Mark McCutcheon's "The Final Theory", (don't pay full price for it, you might wish you hadn't).  He believes there is no gravity, and explains why.  When you have finished picking his arguments to bits, see where you stand on the subject of gravity. ::)
 

Offline Bored chemist

  • Neilep Level Member
  • ******
  • Posts: 8661
  • Thanked: 42 times
    • View Profile
Discussion against gravity
« Reply #19 on: 15/11/2010 19:21:38 »
We have been here before.
http://www.thenakedscientists.com/forum/index.php?topic=10285.0
It was bollocks then, and it still is.
 

Offline maffsolo

  • Sr. Member
  • ****
  • Posts: 280
    • View Profile
Discussion against gravity
« Reply #20 on: 16/11/2010 03:39:51 »
F=M*A
 
M is Mass in units of KiloGrams
A is Gravity in unit of m/s²

F is Force KG*m/s² ...or... a force called a  Newton

Earths gravity is measured and defined in units of acceleration, not in units of force.

Its affects on any mass of any size is a constantly acceleration of 9.81 meters per second squared
The acceleration's rate of change, will be the same, on any mass in a vacuum in the same gravitational field. 

« Last Edit: 16/11/2010 03:41:53 by maffsolo »
 

Offline syedbukhari39

  • Jr. Member
  • **
  • Posts: 24
    • View Profile
Discussion against gravity
« Reply #21 on: 16/11/2010 10:44:17 »
but question is that why is gravity dependent of air?
 

Offline imatfaal

  • Neilep Level Member
  • ******
  • Posts: 2787
  • rouge moderator
    • View Profile
Discussion against gravity
« Reply #22 on: 16/11/2010 11:02:59 »
but question is that why is gravity dependent of air?
  - it isn't.  Gravity 'depends' on mass and distance.  Perhaps read up on the basics on wikipedia
 

Offline syedbukhari39

  • Jr. Member
  • **
  • Posts: 24
    • View Profile
Discussion against gravity
« Reply #23 on: 16/11/2010 11:07:21 »
According to gravitational law, very massive particle in the universe attracts every other massive particle with a force which is directly proportional to the product of their masses and inversely proportional to the square of the distance between them.
By using the formula G*m1*m2/dē
 Calculated value of force between Earth and Moon is 2.1233E20 N approx
and between Sun and Moon is 4.351E20 N approx. which is much higher than the force between Earth and Moon. Then how is the solar system working and existing in the light of Gravitational force? It is quite illogical and false to explain the Solar system through Gravitational force.

By keeping in mind how can you justify and balance the force between Earth, Sun and the Moon when there is a total eclipse of Sun or in normal conditions.
 

Offline peppercorn

  • Neilep Level Member
  • ******
  • Posts: 1466
    • View Profile
    • solar
Discussion against gravity
« Reply #24 on: 16/11/2010 12:53:35 »
According to gravitational law, every very massive particle [with mass] in the universe attracts every other massive particle [with mass] with a force which is directly proportional to the product of their masses and inversely proportional to the square of the distance between them.
Gravitation isn't limited to large objects - every atom (or any other particle with mass) attracts every other.

By keeping in mind how can you justify and balance the force between Earth, Sun and the Moon when there is a total eclipse of Sun or in normal conditions.
In what way could you possibly think that an eclipse would have any impact on gravitation?
 

The Naked Scientists Forum

Discussion against gravity
« Reply #24 on: 16/11/2010 12:53:35 »

 

SMF 2.0.10 | SMF © 2015, Simple Machines
SMFAds for Free Forums