[stack]

The acceleration because of the rotation of the earth is vertical, not horizontal. There is no sideways pull on us because of it so far as I can gather from the links above about the physics of circular motion.

https://www.physicsclassroom.com/class/circles/Lesson-1/Acceleration

And since velocity is a vector that has both magnitude and direction, a change in either the magnitude or the direction constitutes a change in the velocity. For this reason, it can be safely concluded that an object moving in a circle at constant speed is indeed accelerating.

...



Direction of the Acceleration Vector

Note in the diagram above that there is a velocity change for an object moving in a circle with a constant speed. A careful inspection of the velocity change vector in the above diagram shows that it points down and to the left. At the midpoint along the arc connecting points A and B, the velocity change is directed towards point C - the center of the circle. The acceleration of the object is dependent upon this velocity change and is in the same direction as this velocity change. The acceleration of the object is in the same direction as the velocity change vector

it doesn't make any sense to compare a vibration to a constant centrifugal force.

a vibration is a change in acceleration.  the centrifugal acceleration for a person standing on the earth's surface is constant.  those are not comparable at all.

If you are standing with the left side of your body facing the acceleration and turn in a complete circle you would be experiencing a change of 200% of the acceleration on the left side of your body when you travel 180 degrees, and then another 200% as you return to your spot. The side of your body is being pulled and pushed in different directions.

From the same article you cited:

"A careful examination of the flame reveals that the flame will point towards the center of the circle, thus indicating that not only is there an acceleration; but that there is an inward acceleration. This is one more piece of observable evidence that indicates that objects moving in a circle at a constant speed experience an acceleration that is directed towards the center of the circle."

Seems that acceleration is directed toward the center of the circle, not side to side, as Gary already pointed out above.

[Tom Bishop]

Why would standing on a static planet create additional pull towards it's surface when the planet starts to rotate?

These articles are talking about the changing velocity angle being adjusted "towards the center" as the circle is put into motion, like with the two modes of v on the circle in the above illustration.

[stack]

Why would standing on a static planet create additional pull towards it's surface when the planet starts to rotate?

I believe these articles are talking about the changing velocity angle being adjusted "towards the center" as the circle is put into motion.

If I'm understanding the article correctly, it's talking about constant circular rotation, not when it starts to rotate. Which is what we are talking about; constant rotation. And I thought your point in citing the article was that circular rotation acceleration does not pull down to the center, but goes side to side. That's what I thought you meant by, "The side of your body is being pulled and pushed in different directions."

But that's not what the article is saying. It's saying, to Gary's point, it's pulling you toward the center.

[Tom Bishop]

Please explain, in your own words, why putting a planet into a constant rotation would cause a greater pull directly downwards towards it's surface.

[stack]

Please explain, in your own words, why putting a planet into a constant rotation would cause a greater pull directly downwards towards it's surface.

What an interesting request.

Ok Professor, in my own words:

You start out with the premise that we should feel the rotation of earth in a horizontal manner.  The example, putting 7 bucks in change in my pocket should make for the physical perception that if I move sideways in one direction or the other I should feel that weight, much like if I were standing upon a rotating earth. When the contention is that a constant rotating earth pulls you toward the center, not side to side, and has literally nothing to do with sideways/horizontal movement nor 7 dollars of change in my pocket.

Then you cite an article about how humans perceive the vibrations of a vibrating building. Which has nothing to do with a constant rotating earth.

Maths ensue, none of which on your part have to do with a constant rotating earth.

Then you cite a study that tested the vibration and its effects from nearby construction equipment on mice. Again, nothing to do with the constant rotation of an earth and it's effect on humans.

When questioned, you state, "Detecting a change in acceleration is a detection of vibration upon your body." Fair enough, but we've been talking all along about constant rotation, not a change. Again, your argument is not germane to the matter at hand; constant rotation.

Then you cite the https://www.physicsclassroom.com/class/circles/Lesson-1/Acceleration piece where you think it supports your contention that rotating is a horizontal vector velocity, when, in actuality, the article states that "objects moving in a circle at a constant speed experience an acceleration that is directed towards the center of the circle." This from the article you cited to seemingly bolster your position and it directly contradicts your position.

Then you go back to your static or "put in motion" notions when all along, for three pages, we've been talking about constant motion, constant rotation. Not starting, not stopping and not static, constant.

And lastly, if you feel I didn't already answer your question, "why putting a planet into a constant rotation would cause a greater pull directly downwards towards it's surface." The answer is: Gravity.

How is that Professor?

[AATW]

Why would standing on a static planet create additional pull towards it's surface when the planet starts to rotate?

It is counter-intuitive, isn't it? And I had to think about it. I think the simple answer is there isn't an additional pull, there's just a pull because of gravity.
Newton's first law of motion states that a body will stay at rest or continue in a straight line unless acted on by a force.
So if you're travelling at 460m/s on the equator but you're on a revolving planet, and thus going round in a circle, then what is stopping you from continuing in a straight line and flying off into space?
There must be a force acting on you which keeps you stuck to the surface.
Luckily there is, it's called gravity.
If we were on a flat earth which had gravity pointing downwards uniformly - or if we were on a flat earth which was accelerating upwards - then there there would be no variation in g across that plane. Unless there are other forces at work and I know you have some fudge about "celestial gravitation" or something.
In the real world, in a rotating frame of reference the acceleration because of the rotation points inwards, thus the force points inwards. We feel that as an outward (not sideways) force which balances out the inwards force.
I guess you can think of it as most of the gravity is keeping you on the ground, but part of it is keeping you moving in a circle. That part is what we feel as centrifugal  force
That's what makes your apparent weight lighter at the equator than at the poles. There is no sideways force. If you're on a merry go round you are thrown outwards, not sideways.
Some info here:

https://en.wikipedia.org/wiki/Centrifugal_force#Weight_of_an_object_at_the_poles_and_on_the_equator

And this video explains it quite well:



One important thing to note here - if you don't understand all this then that's fine. Honestly, I'm struggling to understand some of it myself.
But you not understanding it doesn't make it wrong.
A common FE argument is basically "I don't understand how..." and the conclusion is that the '...' most be wrong because the person doesn't understand it.
That's not how things work. The truth remains true regardless of what you believe or understand.

[Tom Bishop]

The answer to this is not "it's just gravity."

Stack posted the following quote:

A careful examination of the flame reveals that the flame will point towards the center of the circle, thus indicating that not only is there an acceleration; but that there is an inward acceleration. This is one more piece of observable evidence that indicates that objects moving in a circle at a constant speed experience an acceleration that is directed towards the center of the circle.

How would objects moving in a circle at a constant speed experience an acceleration towards the center of the circle?

The answer is on the same page:

https://www.physicsclassroom.com/class/circles/Lesson-1/Acceleration

At the midpoint along the arc connecting points A and B, the velocity change is directed towards point C - the center of the circle.

It is not talking about a downwards pull towards the center of the circle at all. It's talking about an acceleration and velocity change that is "directed towards" the center as the circle rotates.

[stack]

The answer to this is not "it's just gravity."

Stack posted the following quote:

A careful examination of the flame reveals that the flame will point towards the center of the circle, thus indicating that not only is there an acceleration; but that there is an inward acceleration. This is one more piece of observable evidence that indicates that objects moving in a circle at a constant speed experience an acceleration that is directed towards the center of the circle.

How would objects moving in a circle at a constant speed experience an acceleration towards the center of the circle?

The answer is on the same page:

https://www.physicsclassroom.com/class/circles/Lesson-1/Acceleration

At the midpoint along the arc connecting points A and B, the velocity change is directed towards point C - the center of the circle.

It is not talking about a downwards pull towards the center of the circle at all. It's talking about an acceleration and velocity change that is "directed towards" the center as the circle rotates.

In the next lesson it states:

"And in accord with Newton's second law of motion, an object which experiences an acceleration must also be experiencing a net force. The direction of the net force is in the same direction as the acceleration. So for an object moving in a circle, there must be an inward force acting upon it in order to cause its inward acceleration."

https://www.physicsclassroom.com/Class/circles/u6l1c.cfm

[Tom Bishop]

In the next lesson it states:

"And in accord with Newton's second law of motion, an object which experiences an acceleration must also be experiencing a net force. The direction of the net force is in the same direction as the acceleration. So for an object moving in a circle, there must be an inward force acting upon it in order to cause its inward acceleration."

https://www.physicsclassroom.com/Class/circles/u6l1c.cfm

And the very next three sentences.. "This is sometimes referred to as the centripetal force requirement. The word centripetal (not to be confused with the F-word centrifugal) means center seeking. For object's moving in circular motion, there is a net force acting towards the center which causes the object to seek the center."

Emphasis not mine. "Seeking" the center != additional straight downwards acceleration caused by circular motion. Velocities A and B in the illustration above are deflected towards the center by the circular motion.

[stack]

In the next lesson it states:

"And in accord with Newton's second law of motion, an object which experiences an acceleration must also be experiencing a net force. The direction of the net force is in the same direction as the acceleration. So for an object moving in a circle, there must be an inward force acting upon it in order to cause its inward acceleration."

https://www.physicsclassroom.com/Class/circles/u6l1c.cfm

And the very next three sentences.. "This is sometimes referred to as the centripetal force requirement. The word centripetal (not to be confused with the F-word centrifugal) means center seeking. For object's moving in circular motion, there is a net force acting towards the center which causes the object to seek the center."

Emphasis not mine. "Seeking" the center != additional straight downwards acceleration caused by circular motion. Velocities A and B in the illustration above are deflected towards the center by the circular motion.

Admittedly, I am lost. What is your contention here? Is it the word "pull" versus "seek"?

[AATW]

In the next lesson it states:

"And in accord with Newton's second law of motion, an object which experiences an acceleration must also be experiencing a net force. The direction of the net force is in the same direction as the acceleration. So for an object moving in a circle, there must be an inward force acting upon it in order to cause its inward acceleration."

https://www.physicsclassroom.com/Class/circles/u6l1c.cfm

And the very next three sentences.. "This is sometimes referred to as the centripetal force requirement. The word centripetal (not to be confused with the F-word centrifugal) means center seeking. For object's moving in circular motion, there is a net force acting towards the center which causes the object to seek the center."

Emphasis not mine. "Seeking" the center != additional straight downwards acceleration caused by circular motion. Velocities A and B in the illustration above are deflected towards the center by the circular motion.

I'm also confused what you're arguing here. The part you've quoted - I've put a bit in bold - is saying exactly what I'm saying and what you appear to be arguing against. The force acts downwards, you feel that as a sensation as being thrown outwards, you don't get knocked sideways. If you've been on a roundabout you know that. And the point is the amount you feel that is around 0.3% of your weight. Enough to measure, not enough to feel.

[RonJ]

It looks like everybody here as an education on Newton's 2nd law.  It really doesn't apply to the earth at all if, according to FET, the earth is not spinning.  You should feel the vertical acceleration force at your feet and that's about it.  It looks to me that Newton's 2nd law would be a critical factor for the moon under FET.   Acceleration is a change in velocity. Velocity is also a vector so acceleration could be either a change in speed or a change in direction, or it could be both at the same time.   Keeping the moon stationary over the flat earth requires a constant acceleration upwards (vertical relative to the surface of the earth).  Keeping the moon in a circular path would require a force sideways (horizontal relative to the surface of the earth).  What is the provider of that force?  The force must be there because you can see a constant change in the moon's velocity, AKA a circular motion.