What is the definition of Uphill?

  • Thread starter Thread starter Averagesupernova
  • Start date Start date
  • Tags Tags
    Definition
Click For Summary
SUMMARY

The discussion centers on the definition of "uphill" in relation to water flow towards the equator. Participants clarify that while water does not universally flow towards the equator, many rivers and streams in the northern hemisphere do trend southward. The conversation highlights the Earth's oblate spheroid shape, which means the equator is technically farther from the center of the Earth, leading to the assertion that water flows "uphill" to the equator. Additionally, the Coriolis effect and gravitational potential energy are discussed as significant factors influencing water movement.

PREREQUISITES
  • Understanding of gravitational potential energy
  • Familiarity with the Coriolis effect
  • Knowledge of Earth's oblate spheroid shape
  • Basic concepts of hydrodynamics
NEXT STEPS
  • Research the Coriolis effect and its impact on ocean currents
  • Explore the concept of gravitational potential energy in fluid dynamics
  • Study the Earth's shape and its implications for geography and hydrology
  • Investigate the flow patterns of major rivers and their relation to elevation
USEFUL FOR

Geographers, hydrologists, environmental scientists, and anyone interested in the dynamics of water flow and Earth's physical properties.

  • #31
Averagesupernova said:
And technically they are. It's not a requirement that they make it all the way to the south pole.
I've looked. Oceans are out, I already told you that. Just delete this thread, I'm tired of it. It's not that I don't get what you are saying, you don't seem to get what I'm saying. Maybe I'm just stupid in that I am unable to communicate it to you (all of you). But I'm tired of it.
You will have an epiphany at 3am and it will all be clear and you will be able to explain it all to us. :smile:

Go eat some oyster crackers. :biggrin:
 
Physics news on Phys.org
  • #32
cyrusabdollahi said:
I don't see what's so funny about that book, I just finished reading all 500 pages of it, and you would learn a lot from it.
I didn't expect you to 'get it' cyrus. So in hindsight I shouldn't have posted. Couldn't help myself. From my point of view though...
 
  • #33
Evo said:
You will have an epiphany at 3am and it will all be clear and you will be able to explain it all to us. :smile:
Go eat some oyster crackers. :biggrin:

I ate them up Evo.
 
  • #34
Averagesupernova said:
I ate them up Evo.
Well, that explains it, make more. :biggrin:
 
  • #35
No, right now I'm thinking Miller Lite.
 
  • #36
Did I tell you about the time I was five and I was certain toliets operated on electricity? :frown: I mean, how else could they flush? :redface:
 
  • #37
:eek: You mean they DON'T? :eek:
The above was intended as sarcasm.
 
  • #40
I just wanted you to flush your misconceptions of rivers flowing north down the....err umm...toilet :smile:
 
  • #41
I remember a list of questions someone (maybe Gokul) posted once. One of the questions was about the Mississippi river flowing up hill and there being a physics reason for doing so. I don't know what the answer was though.

As far as where water flows to I've figured out that any spilled water flows to the spot where I am about to step if I'm wearing socks.
 
  • #42
If I may...

Perhaps what the OP is asking is...

Why would ANY rivers flow towards the equator, since, as we know from the shape of the Earth, the equator is higher than the poles. Any rivers that flow toward the equator will effectively be climbing uphill, right?

Here is the answer:

Consider what sea level is in these various parts of the Earth. Sea level is the lowest possible point to which water will flow. If sea level near the equator really WERE higher than at the poles - well, logically, the equatorial seas would be bone dry beaches wouldn't they?

But the fact that the Earth is an oblate spheroid also means that its gravitational pull is not distributed evenly. The net effect is that every point on the Earth's surface experiences approximately the same amount of pull. This means that the equator is NOT "downhill" from the North Pole regardless of their relative distances from the geometric centre of the Earth.

All water in the oceans (including the water that the Mississippi flows into) is at the lowest point it can go. The Mississippi flows downhill towards it.
 
  • #43
DaveC426913 said:
But the fact that the Earth is an oblate spheroid also means that its gravitational pull is not distributed evenly. The net effect is that every point on the Earth's surface experiences approximately the same amount of pull.
I can't follow this. The second sentence seems to be presented as explaining a consequence of the first, but in fact, seems to contradict it. If the pull is not evenly distributed than why would you say every point experiences the same amount of pull?
 
  • #44
zoobyshoe said:
I can't follow this. The second sentence seems to be presented as explaining a consequence of the first, but in fact, seems to contradict it. If the pull is not evenly distributed than why would you say every point experiences the same amount of pull?
The facts that 1] the pull is not distributed spherically AND 2] that the Earth is not spherical, cancel each other out, such that any point on the Earth (at sea level) experiences the same amount of pull, and it is perpendicular to the surface.

Forget rivers for a second. Oceans are simpler. If the Caribbean Sea really *were* uphill from the Arctic ocean, the water would flow out of the Caribbean into the Arctic, leaving the Caribbean bone-dry.

The fact is, sea level EVERYWHERE on the Earth is the lowest point at which water can flow to.

Have a look at the attached pic.
 
Last edited:
  • #45
Wow, I'm finding this really hard to explain succinctly.

The gravitational pull at any point on the surface of a perfect sphere happens to be exactly in the direction of the centre of the sphere. The line on a plumb bob will point at the physical centre of the sphere.

No so with other objects.

The gravitational pull on the surface of an oblate spheroid is NOT always inline with the physical centre of the object. A plumb bob, if followed through the object will point to different places, depending on where you are standing.

HOWEVER, the plumb bob line will ALWAYS be tangential to the surface where you are standing. That means every point on an oblate spheroid is experienced as horizontal - no sloping effect.
 
  • #46
:wink: Good luck Dave!
 

Similar threads

  • · Replies 33 ·
2
Replies
33
Views
719
Replies
21
Views
8K
  • · Replies 28 ·
Replies
28
Views
3K
  • · Replies 5 ·
Replies
5
Views
3K
  • · Replies 18 ·
Replies
18
Views
2K
  • · Replies 21 ·
Replies
21
Views
4K
  • · Replies 5 ·
Replies
5
Views
4K
  • · Replies 7 ·
Replies
7
Views
9K
  • · Replies 42 ·
2
Replies
42
Views
7K
  • · Replies 1 ·
Replies
1
Views
3K