Why doesn't tidal force pull earth and moon together?

In summary, the conversation discusses the concept of tidal forces and how they create two tidal bulges on Earth, as well as the common misconception of using centrifugal force to explain the tides. The conversation also highlights the importance of understanding non-uniform gravitational fields in explaining the tides, as well as referencing a reliable source for further information.
  • #1
AlonsoMcLaren
90
2
Why does tidal force strectechs the Earth and creates two tidal bulges, like pulling on a rubber band, instead of pulling Earth and moon together?
 
Astronomy news on Phys.org
  • #2
Check out
http://tidesandcurrents.noaa.gov/publications/Understanding_Tides_by_Steacy_finalFINAL11_30.pdf"
 
Last edited by a moderator:
  • #3
Gannet said:
Check out
http://tidesandcurrents.noaa.gov/publications/Understanding_Tides_by_Steacy_finalFINAL11_30.pdf"
*Sigh*

Oceanographers use the wrong explanation. Almost inevitably. It is a bad, bad meme in the oceanography world. While oceanographers do do oceanography well, that doesn't extend to physics. You don't need centrifugal force to explain the tides, centrifugal force does not explain the tides, and what they are calling centrifugal force is not the centrifugal force! The tide generating forces are the result of a non-uniform gravitational field. Period.

A few oceanographers do get it right. This article, http://oceanworld.tamu.edu/resources/ocng_textbook/chapter17/chapter17_04.htm, is a bit better than most. As much as people like to malign wikipedia, their suite of articles on the tides are pretty dang good.
 
Last edited by a moderator:
  • #4
D H said:
*Sigh*...

Hicks does get into differential tidal forces in Chapter 5, which I think is very well explicitly defined and takes into account both lunar and solar tidal generating forces. That's why I lead the OP to this document.
 
  • #5
Gannet said:
Hicks does get into differential tidal forces in Chapter 5, which I think is very well explicitly defined and takes into account both lunar and solar tidal generating forces. That's why I lead the OP to this document.
Ahh. So Hicks does. So why that nonsense in chapter 1?
 

1. Why doesn't the tidal force pull the Earth and Moon together?

The tidal force is the result of the gravitational pull of the Moon on the Earth's oceans. This force is not strong enough to pull the Earth and Moon together because the Earth's gravity is much stronger and holds the Moon in orbit.

2. How does the Earth's gravity keep the Moon in orbit?

The Earth's gravity is what keeps the Moon in its orbit. The Moon is constantly falling towards the Earth, but its tangential velocity is enough to keep it in a circular orbit around the Earth.

3. Does the distance between the Earth and Moon affect the strength of the tidal force?

Yes, the strength of the tidal force is inversely proportional to the distance between the Earth and Moon. This means that the closer the Moon is to the Earth, the stronger the tidal force will be.

4. Are there any other factors besides gravity that affect the strength of the tidal force?

Yes, the shape and size of the bodies involved can also affect the strength of the tidal force. The Earth's oceans are more easily pulled towards the Moon due to their fluidity, while the solid Earth is less affected.

5. Could the tidal force eventually pull the Moon out of orbit?

No, the Moon's orbit is stable and will not be affected by the tidal force. The Moon's distance from the Earth and its velocity are just right to keep it in a stable orbit around the Earth.

Similar threads

I Why Do Stars in Binary Systems Assume a Teardrop Shape?
    • Astronomy and Astrophysics
Replies
14
Views
693
I Tidal effects on Earth's rotation and moon's orbit
    • Astronomy and Astrophysics
Replies
10
Views
2K
I Tidal forces acting on planet NGTS-10b
    • Astronomy and Astrophysics
Replies
2
Views
2K
B Earth & Moon Gravity Gradient: Investigating Its Impact
    • Astronomy and Astrophysics
Replies
33
Views
3K
I A New Idea for the Origin of Earth's Water
    • Astronomy and Astrophysics
Replies
1
Views
1K
I Question about Moon's gravitational effect on tidal bulge
    • Classical Physics
Replies
15
Views
1K
B What Are Love Numbers and How Do They Impact Tidal Deformations?
    • Astronomy and Astrophysics
Replies
6
Views
2K
Tidal friction and global warming
    • Earth Sciences
Replies
10
Views
320
B Why can we only see one side of the moon?
    • Astronomy and Astrophysics
Replies
13
Views
2K
I Question about a magnetic dynamo on tidally locked moons
    • Astronomy and Astrophysics
Replies
7
Views
2K

Hot Threads

Recent Insights

Back
Top