Question about the Foucault's Pendulum?

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sokarul

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Re: Question about the Foucault's Pendulum?
« Reply #60 on: June 18, 2020, 01:23:58 PM »
Those are velocities. Objects don’t feel velocity.
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JJA

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Re: Question about the Foucault's Pendulum?
« Reply #61 on: June 18, 2020, 02:44:33 PM »
Quote
only once every 24 hours
rotation is non-stop therefore time is not a factor. It can be observed for many many years if possible. It will show a noticeable rise/ spill at the east of container one day

"Once every 24 hours" is a unit of speed, not time.  I was pointing out how SLOW the rotation was.  If a rotation is slow, the effect is small, and rotating at 0.0007 RPM is very very very very slow.

A glass of water on a platform rotating at 0.0007 RPM simply isn't going to show a visible effect. 

You can try this at home.  Here is something that runs at 1 RPM, a thousand times faster than the Earth, you can put a cup of water on there and see if you can spot any spilling of the water. Then remember the Earth is a thousand times slower.

https://www.amazon.com/dp/B0756ZQX42/
460 meters per second or roughly 1,000 miles per hour is not enough to show leaning in the aforementioned water or any water bodies.

1000 miles an hour going around a 30 foot merry go round would probably kill you.

1000 miles an hour going around a planet 8,000 miles in diameter means you hardly feel it.

It's all about scale.

So no, 1000 miles an hour when it's 24,000 miles to make one rotation means it's rotating VERY SLOWLY.

Too slow to show any lean.  And remember that lean will be UP, not to the east.

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rabinoz

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Re: Question about the Foucault's Pendulum?
« Reply #62 on: June 18, 2020, 07:25:56 PM »
Quote
only once every 24 hours
rotation is non-stop therefore time is not a factor. It can be observed for many many years if possible. It will show a noticeable rise/ spill at the east of container one day
The Coriolis force has nothing to do with the velocity of the Earth's surface but only the angular velocity of the Earth's rotation and the velocity of the "particle" - air , water etc.

The strongest Coriolis force would be near either pole where the velocity is near zero.

The following expression is from: Coriolis force
The Coriolis force on a particle depends on  the angular velocity times the velocity of the particle towards the centre of rotation as in ,
where: m is the mass of the particle, Ω and v' is the particle velocity in the rotating frame - ie on Earth. The × is the vector cross product and means we use the component of v' at right angles to the axis of rotation

On Earth, the rate of rotation is close to 360°/24 hours or about 7.29 × 10−5/sec.
So for air or water at 45° latitude moving at 10 m/s (36 km/hr) acceleration would only be about 0.001 m/s2 (the same as a force of 0.001 N/kg) - it is minute (unless I've made a mistake ;D).

The Coriolis effect isn't going to "pile anything up" see Coriolis Acceleration and Scales of Circulation.

Re: Question about the Foucault's Pendulum?
« Reply #63 on: June 18, 2020, 11:28:42 PM »
How about a balanced pencil on its pointed end. it could be similar anything of greater height. Would it fall east (day time) or west (night time)? - I know the answer will be NO from your side.

similarly, there is a Coriolis effect on the surface water and wind but the velocity (30 km/sec) of the earth in its orbit around the sun has no effect on wind, atmosphere or water - no idea 
« Last Edit: June 19, 2020, 12:30:53 AM by E E K »

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JJA

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Re: Question about the Foucault's Pendulum?
« Reply #64 on: June 19, 2020, 04:00:07 AM »
How about a balanced pencil on its pointed end. it could be similar anything of greater height. Would it fall east (day time) or west (night time)? - I know the answer will be NO from your side.

You are correct, we would say no, it would not fall over, because that's not how forces like that work.

Think of the classic experiment where you put a bucket of water on a rope and swing it around you as fast as you can.

Where does the water go?  It goes to the bottom of the bucket.  It goes away from you.  The same with the spinning Earth, the force will try and send things away from it, not sideways.

Here is a diagram to illustrate.  The force is AWAY from the man spinning the weight.  That's why when you swing something around the rope goes away from you, not sideways.



similarly, there is a Coriolis effect on the surface water and wind but the velocity (30 km/sec) of the earth in its orbit around the sun has no effect on wind, atmosphere or water - no idea

The Earth doesn't feel a force from it's orbit around the Sun, it's in free-fall around the Sun.  It's the same as astronauts aboard the ISS. They aren't being thrown around because they are in orbit, they are weightless. The Earth is not locked physically to the Sun like you are the surface of the Earth when standing on it.

Re: Question about the Foucault's Pendulum?
« Reply #65 on: June 19, 2020, 05:31:46 AM »
How about a balanced pencil on its pointed end. it could be similar anything of greater height. Would it fall east (day time) or west (night time)? - I know the answer will be NO from your side.

You are correct, we would say no, it would not fall over, because that's not how forces like that work.

Think of the classic experiment where you put a bucket of water on a rope and swing it around you as fast as you can.

Where does the water go?  It goes to the bottom of the bucket.  It goes away from you.  The same with the spinning Earth, the force will try and send things away from it, not sideways.

Here is a diagram to illustrate.  The force is AWAY from the man spinning the weight.  That's why when you swing something around the rope goes away from you, not sideways.



similarly, there is a Coriolis effect on the surface water and wind but the velocity (30 km/sec) of the earth in its orbit around the sun has no effect on wind, atmosphere or water - no idea

The Earth doesn't feel a force from it's orbit around the Sun, it's in free-fall around the Sun.  It's the same as astronauts aboard the ISS. They aren't being thrown around because they are in orbit, they are weightless. The Earth is not locked physically to the Sun like you are the surface of the Earth when standing on it.
That’s what I was explaining to you. Do you remember the example of Saudi Clerik, contact, and non-contact gravitational forces that I had mentioned earlier? 

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rabinoz

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Re: Question about the Foucault's Pendulum?
« Reply #66 on: June 19, 2020, 05:43:45 AM »
How about a balanced pencil on its pointed end. it could be similar anything of greater height. Would it fall east (day time) or west (night time)? - I know the answer will be NO from your side.

You are correct, we would say no, it would not fall over, because that's not how forces like that work.

Think of the classic experiment where you put a bucket of water on a rope and swing it around you as fast as you can.

Where does the water go?  It goes to the bottom of the bucket.  It goes away from you.  The same with the spinning Earth, the force will try and send things away from it, not sideways.

Here is a diagram to illustrate.  The force is AWAY from the man spinning the weight.  That's why when you swing something around the rope goes away from you, not sideways.



similarly, there is a Coriolis effect on the surface water and wind but the velocity (30 km/sec) of the earth in its orbit around the sun has no effect on wind, atmosphere or water - no idea

The Earth doesn't feel a force from it's orbit around the Sun, it's in free-fall around the Sun.  It's the same as astronauts aboard the ISS. They aren't being thrown around because they are in orbit, they are weightless. The Earth is not locked physically to the Sun like you are the surface of the Earth when standing on it.
That’s what I was explaining to you. Do you remember the example of Saudi Clerik, contact, and non-contact gravitational forces that I had mentioned earlier?
But that has nothing to do with the Coriolis effect and Fouclault pendulums!

Re: Question about the Foucault's Pendulum?
« Reply #67 on: June 19, 2020, 08:03:35 AM »
How about a balanced pencil on its pointed end. it could be similar anything of greater height. Would it fall east (day time) or west (night time)? - I know the answer will be NO from your side.

You are correct, we would say no, it would not fall over, because that's not how forces like that work.

Think of the classic experiment where you put a bucket of water on a rope and swing it around you as fast as you can.

Where does the water go?  It goes to the bottom of the bucket.  It goes away from you.  The same with the spinning Earth, the force will try and send things away from it, not sideways.

Here is a diagram to illustrate.  The force is AWAY from the man spinning the weight.  That's why when you swing something around the rope goes away from you, not sideways.



similarly, there is a Coriolis effect on the surface water and wind but the velocity (30 km/sec) of the earth in its orbit around the sun has no effect on wind, atmosphere or water - no idea

The Earth doesn't feel a force from it's orbit around the Sun, it's in free-fall around the Sun.  It's the same as astronauts aboard the ISS. They aren't being thrown around because they are in orbit, they are weightless. The Earth is not locked physically to the Sun like you are the surface of the Earth when standing on it.
That’s what I was explaining to you. Do you remember the example of Saudi Clerik, contact, and non-contact gravitational forces that I had mentioned earlier?
But that has nothing to do with the Coriolis effect and Fouclault pendulums!
Earth doesn’t rotate below the airplanes or suspended pendulum either stationary or swinging in the air. They including the atmosphere move along with the Earth's rotation. Earth's spinning has no effect on the landing or taking off of planes, birds sitting on trees or elsewhere, etc because their motion is inertial to earth. It’s all relative to the Earth.



00:17 - 1:48 "All free-moving objects including masses of air on earth are subjected to Coriolis effect". 

Why? when there is no rotating frame (like merry go round) in between the earth and masses of the air?
« Last Edit: June 19, 2020, 11:12:01 AM by E E K »

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rabinoz

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Re: Question about the Foucault's Pendulum?
« Reply #68 on: June 19, 2020, 04:11:32 PM »
But that has nothing to do with the Coriolis effect and Fouclault pendulums!
Earth doesn’t rotate below the airplanes
Because, as has been explained numerous times, the airplanes are flying in the air and are navigated to their destination.
You might notice that are designed to be controlled by the air-flow. They have both vertical and horizontal control surfaces for exactly that purpose.

Quote from: E E K
or suspended pendulum either stationary or swinging in the air. They including the atmosphere move along with the Earth's rotation.
Because Foucault pendulums are purposely made very heavy so that the air will have virtually no effect on them.

Quote from: E E K
Earth's spinning has no effect on the landing or taking off of planes, birds sitting on trees or elsewhere, etc because their motion is inertial to earth. It’s all relative to the Earth.
Why should it? The planes are taking of from the Earth in air that (apart from local winds) that is all moving together.

Quote from: E E K


00:17 - 1:48 "All free-moving objects including masses of air on earth are subjected to Coriolis effect". 

Why? when there is no rotating frame (like merry go round) in between the earth and masses of the air?
Air (or anything else) moving from a part of the Earth moving at one velocity to another moving at a different velocity will be subject "subjected to Coriolis effect".
It is a very slight effect and is quite negligible on planes or cars that are directed but other means.
But the effect can be seen on the movement or air, water or projectiles (artillery) move South to North or North to South and this must be taken into account when shooting at long range - tens of kilometers.

But, if you want big Coriolis, here's big Coriolis and long-range artillery, and the Coriolis Effect, try the "Paris Gun" used by Germany in WW I. It's at ranges like thus where the Coriolis and Eötvös effects become essential.

Have a look at:
Quote from: G. Trifkovic

In June 2002 issue of Military Heritage there is an article on Paris gun and a good part of it is about calculations that needed to be done in order to ensure accuracy. So,the Germans digged out the works of one Gustave Gaspard Coriolis (1792-1843),who in 1835 published his Sur les Equations du Mouvement Relatif des Systemes de Corps ("On the equations of Relative Motion of System of Bodies"),in which he stated that ,due to spherical nature of the Earth and it's rotation, a moving object on a north-south vector would be affected by the relative rotational speeds of launch and impact points. Earlier German use of long-range guns (firing from Lugenboom on Dunkirk), didn't have to take into account Coriolis Effect, because the firing site and target were on an east-west axis. Obscure mathematician von Eberhardt, at the time working for Krupp, understood the problems of firing on the north-south axis, so he based his research on Coriolis' works and made calculations accordingly.
Being advised on the site of the gun (Crepy-an-Laonnois), he estimated rotational speed of Paris at 567 mph on the 49th parallel and that of Laon at 555.55mph on the 48th parallel.So, an adjustment of 11.58 mph had to be provided for the laying of the gun. Also, he calculated the estimated flight time at 176 seconds and this called for easterly correction of 0.566 miles to compensate for differing rotational speeds of gun and target.
I am not too keen on math  ::) but this article really captured me, showing how much hard work (apart from technical aspects) was needed just to fire this gun. And all this was done without computer...  :o

Cheers,

GAius

From: Axis History Forum, The Paris Gun

Re: Question about the Foucault's Pendulum?
« Reply #69 on: June 20, 2020, 12:08:52 AM »
I may be wrong but there are no such free moving objects like masses of air on earth. Free means Earth’s gravity has no effect on them at all. It’s only possible if moving with escape velocity. Temperature and pressure play an important role in their moving but it doesn’t mean that they move freely w/o the effect of gravity on them.

We know the air is a mixture of different gasses at different temperatures and pressure therefore the center of gravity of the whole mass of air might change its place wrt the earth which may be the reason for changing the direction of movement of air.

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rabinoz

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Re: Question about the Foucault's Pendulum?
« Reply #70 on: June 20, 2020, 01:23:01 AM »
I may be wrong but there are no such free moving objects like masses of air on earth. Free means Earth’s gravity has no effect on them at all. It’s only possible if moving with escape velocity. Temperature and pressure play an important role in their moving but it doesn’t mean that they move freely w/o the effect of gravity on them.

We know the air is a mixture of different gasses at different temperatures and pressure therefore the center of gravity of the whole mass of air might change its place wrt the earth which may be the reason for changing the direction of movement of air.
How is any of that relevant to the Coriolis effect and the related action the Foucault Pendulum?

Gravity accelerates a projectile down towards the Earth but the Coriolis acceleration is at right angles to that.
And the Coriolis effect is certainly observed and must be allowed for in the aiming of long-range artillery.

Likewise gravity makes the Foucault Pendulum swing but, at least at either pole, has no effect on the direction of the swing.

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sceptimatic

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Re: Question about the Foucault's Pendulum?
« Reply #71 on: June 20, 2020, 03:18:19 AM »
Those are velocities. Objects don’t feel velocity.
Objects do feel velocity.

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JJA

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Re: Question about the Foucault's Pendulum?
« Reply #72 on: June 20, 2020, 04:17:12 AM »
Those are velocities. Objects don’t feel velocity.
Objects do feel velocity.

No objects do not feel velocity.  When you are sitting in an airplane flying at cruising altitude at 500mph, you don't "feel" hat 500mph, do you?  It feels like you are sitting still. There is no way for you to know without looking out the window or using a GPS if you are going 50mph or 500mph.

Re: Question about the Foucault's Pendulum?
« Reply #73 on: June 20, 2020, 08:08:08 AM »
Rotation of earth does change the direction of the vertical plane in which the Foucault's pendulum swings due to the weight of the bob when it comes to rest at its two extreme ends during swinging. 

Apropos the direction of swing in between the two ends:

Earth rotates about its axis at a rate of 460 meters per second. I believe a plumb bob of considerable size hits exactly at its plumb target on the ground if it drops from the top of Burj Khalifa which is 830 m high under the control environment, which doesn’t affect falling of bob.

According to Foucault believers, it should deviate its plumb target on the ground due to the rotation of the earth – Right?

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JJA

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Re: Question about the Foucault's Pendulum?
« Reply #74 on: June 20, 2020, 09:22:28 AM »
Rotation of earth does change the direction of the vertical plane in which the Foucault's pendulum swings due to the weight of the bob when it comes to rest at its two extreme ends during swinging. 

Apropos the direction of swing in between the two ends:

Earth rotates about its axis at a rate of 460 meters per second. I believe a plumb bob of considerable size hits exactly at its plumb target on the ground if it drops from the top of Burj Khalifa which is 830 m high under the control environment, which doesn’t affect falling of bob.

According to Foucault believers, it should deviate its plumb target on the ground due to the rotation of the earth – Right?

The Earth rotates once every 24 hours, or 0.0007 RPM.  You are moving 460 m/s on the surface.

If you hang a pendulum from the Burj Khalifa and swing it long enough then yes, it will rotate.

This is because a pendulum, a gyroscope, a flywheel or a mass supported on a frictionless surface will want to keep it's orientation unless an external force acts upon it.

Re: Question about the Foucault's Pendulum?
« Reply #75 on: June 20, 2020, 09:59:15 AM »
Rotation of earth does change the direction of the vertical plane in which the Foucault's pendulum swings due to the weight of the bob when it comes to rest at its two extreme ends during swinging. 

Apropos the direction of swing in between the two ends:

Earth rotates about its axis at a rate of 460 meters per second. I believe a plumb bob of considerable size hits exactly at its plumb target on the ground if it drops from the top of Burj Khalifa which is 830 m high under the control environment, which doesn’t affect falling of bob.

According to Foucault believers, it should deviate its plumb target on the ground due to the rotation of the earth – Right?

The Earth rotates once every 24 hours, or 0.0007 RPM.  You are moving 460 m/s on the surface.

If you hang a pendulum from the Burj Khalifa and swing it long enough then yes, it will rotate.

This is because a pendulum, a gyroscope, a flywheel or a mass supported on a frictionless surface will want to keep it's orientation unless an external force acts upon it.
I said if dropped (the only bob, not along with its wire)

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JJA

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Re: Question about the Foucault's Pendulum?
« Reply #76 on: June 20, 2020, 10:57:13 AM »
Rotation of earth does change the direction of the vertical plane in which the Foucault's pendulum swings due to the weight of the bob when it comes to rest at its two extreme ends during swinging. 

Apropos the direction of swing in between the two ends:

Earth rotates about its axis at a rate of 460 meters per second. I believe a plumb bob of considerable size hits exactly at its plumb target on the ground if it drops from the top of Burj Khalifa which is 830 m high under the control environment, which doesn’t affect falling of bob.

According to Foucault believers, it should deviate its plumb target on the ground due to the rotation of the earth – Right?

The Earth rotates once every 24 hours, or 0.0007 RPM.  You are moving 460 m/s on the surface.

If you hang a pendulum from the Burj Khalifa and swing it long enough then yes, it will rotate.

This is because a pendulum, a gyroscope, a flywheel or a mass supported on a frictionless surface will want to keep it's orientation unless an external force acts upon it.
I said if dropped (the only bob, not along with its wire)

If you dropped it the plumb would deviate as the earth rotated under it, but that short a distance it would be hard to measure with much accuracy due to wind and other environmental effects. If you built a vacuum chamber that big it would be easy to measure if you dropped a smaller object.

Bullets and artillery shells are better demonstrations of the Coriolis effect.

Details and math - https://www.dpmms.cam.ac.uk/~stcs/courses/dynamics/handouts/handout5a.pdf

Re: Question about the Foucault's Pendulum?
« Reply #77 on: June 20, 2020, 11:23:54 AM »
Rotation of earth does change the direction of the vertical plane in which the Foucault's pendulum swings due to the weight of the bob when it comes to rest at its two extreme ends during swinging. 

Apropos the direction of swing in between the two ends:

Earth rotates about its axis at a rate of 460 meters per second. I believe a plumb bob of considerable size hits exactly at its plumb target on the ground if it drops from the top of Burj Khalifa which is 830 m high under the control environment, which doesn’t affect falling of bob.

According to Foucault believers, it should deviate its plumb target on the ground due to the rotation of the earth – Right?

The Earth rotates once every 24 hours, or 0.0007 RPM.  You are moving 460 m/s on the surface.

If you hang a pendulum from the Burj Khalifa and swing it long enough then yes, it will rotate.

This is because a pendulum, a gyroscope, a flywheel or a mass supported on a frictionless surface will want to keep it's orientation unless an external force acts upon it.
I said if dropped (the only bob, not along with its wire)

If you dropped it the plumb would deviate as the earth rotated under it, but that short a distance it would be hard to measure with much accuracy due to wind and other environmental effects. If you built a vacuum chamber that big it would be easy to measure if you dropped a smaller object.

Bullets and artillery shells are better demonstrations of the Coriolis effect.

Details and math - https://www.dpmms.cam.ac.uk/~stcs/courses/dynamics/handouts/handout5a.pdf
since all masses fall at the same rate, therefore, how about the idea of trying with the bob of Foucault's pendulum on a day determined by mereological conditions instead of building a vacuum chamber. 

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JJA

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Re: Question about the Foucault's Pendulum?
« Reply #78 on: June 20, 2020, 11:37:16 AM »
Rotation of earth does change the direction of the vertical plane in which the Foucault's pendulum swings due to the weight of the bob when it comes to rest at its two extreme ends during swinging. 

Apropos the direction of swing in between the two ends:

Earth rotates about its axis at a rate of 460 meters per second. I believe a plumb bob of considerable size hits exactly at its plumb target on the ground if it drops from the top of Burj Khalifa which is 830 m high under the control environment, which doesn’t affect falling of bob.

According to Foucault believers, it should deviate its plumb target on the ground due to the rotation of the earth – Right?

The Earth rotates once every 24 hours, or 0.0007 RPM.  You are moving 460 m/s on the surface.

If you hang a pendulum from the Burj Khalifa and swing it long enough then yes, it will rotate.

This is because a pendulum, a gyroscope, a flywheel or a mass supported on a frictionless surface will want to keep it's orientation unless an external force acts upon it.
I said if dropped (the only bob, not along with its wire)

If you dropped it the plumb would deviate as the earth rotated under it, but that short a distance it would be hard to measure with much accuracy due to wind and other environmental effects. If you built a vacuum chamber that big it would be easy to measure if you dropped a smaller object.

Bullets and artillery shells are better demonstrations of the Coriolis effect.

Details and math - https://www.dpmms.cam.ac.uk/~stcs/courses/dynamics/handouts/handout5a.pdf
since all masses fall at the same rate, therefore, how about the idea of trying with the bob of Foucault's pendulum on a day determined by mereological conditions instead of building a vacuum chamber.

Wind is always random and erratic, but the idea is sound.  If you drop a weight far enough, it will drift due to the Coriolis effect, yes.

Re: Question about the Foucault's Pendulum?
« Reply #79 on: June 20, 2020, 01:53:20 PM »
Rotation of earth does change the direction of the vertical plane in which the Foucault's pendulum swings due to the weight of the bob when it comes to rest at its two extreme ends during swinging. 

Apropos the direction of swing in between the two ends:

Earth rotates about its axis at a rate of 460 meters per second. I believe a plumb bob of considerable size hits exactly at its plumb target on the ground if it drops from the top of Burj Khalifa which is 830 m high under the control environment, which doesn’t affect falling of bob.

According to Foucault believers, it should deviate its plumb target on the ground due to the rotation of the earth – Right?

The Earth rotates once every 24 hours, or 0.0007 RPM.  You are moving 460 m/s on the surface.

If you hang a pendulum from the Burj Khalifa and swing it long enough then yes, it will rotate.

This is because a pendulum, a gyroscope, a flywheel or a mass supported on a frictionless surface will want to keep it's orientation unless an external force acts upon it.
I said if dropped (the only bob, not along with its wire)

If you dropped it the plumb would deviate as the earth rotated under it, but that short a distance it would be hard to measure with much accuracy due to wind and other environmental effects. If you built a vacuum chamber that big it would be easy to measure if you dropped a smaller object.

Bullets and artillery shells are better demonstrations of the Coriolis effect.

Details and math - https://www.dpmms.cam.ac.uk/~stcs/courses/dynamics/handouts/handout5a.pdf
since all masses fall at the same rate, therefore, how about the idea of trying with the bob of Foucault's pendulum on a day determined by mereological conditions instead of building a vacuum chamber.

Wind is always random and erratic, but the idea is sound.  If you drop a weight far enough, it will drift due to the Coriolis effect, yes.
True, wind may interrupt but at least we can test the idea if a controlled environment is not possible. Similarly, we can monitor the whole experiment by installing

1-   Laser light inside the pointed end of the bob (hollow cone-type nozzle).
2-   At least two video cameras; one totally focusing at the target on the ground and the other at the tip of a nozzle for observing the deviation of laser light from its target all the way from the start point to the target and the spinning of the earth.
3-   The latest available technology of the time.

It was nice chatting with all -TY- Have a good one!

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JJA

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Re: Question about the Foucault's Pendulum?
« Reply #80 on: June 21, 2020, 04:04:22 AM »
Rotation of earth does change the direction of the vertical plane in which the Foucault's pendulum swings due to the weight of the bob when it comes to rest at its two extreme ends during swinging. 

Apropos the direction of swing in between the two ends:

Earth rotates about its axis at a rate of 460 meters per second. I believe a plumb bob of considerable size hits exactly at its plumb target on the ground if it drops from the top of Burj Khalifa which is 830 m high under the control environment, which doesn’t affect falling of bob.

According to Foucault believers, it should deviate its plumb target on the ground due to the rotation of the earth – Right?

The Earth rotates once every 24 hours, or 0.0007 RPM.  You are moving 460 m/s on the surface.

If you hang a pendulum from the Burj Khalifa and swing it long enough then yes, it will rotate.

This is because a pendulum, a gyroscope, a flywheel or a mass supported on a frictionless surface will want to keep it's orientation unless an external force acts upon it.
I said if dropped (the only bob, not along with its wire)

If you dropped it the plumb would deviate as the earth rotated under it, but that short a distance it would be hard to measure with much accuracy due to wind and other environmental effects. If you built a vacuum chamber that big it would be easy to measure if you dropped a smaller object.

Bullets and artillery shells are better demonstrations of the Coriolis effect.

Details and math - https://www.dpmms.cam.ac.uk/~stcs/courses/dynamics/handouts/handout5a.pdf
since all masses fall at the same rate, therefore, how about the idea of trying with the bob of Foucault's pendulum on a day determined by mereological conditions instead of building a vacuum chamber.

Wind is always random and erratic, but the idea is sound.  If you drop a weight far enough, it will drift due to the Coriolis effect, yes.
True, wind may interrupt but at least we can test the idea if a controlled environment is not possible. Similarly, we can monitor the whole experiment by installing

1-   Laser light inside the pointed end of the bob (hollow cone-type nozzle).
2-   At least two video cameras; one totally focusing at the target on the ground and the other at the tip of a nozzle for observing the deviation of laser light from its target all the way from the start point to the target and the spinning of the earth.
3-   The latest available technology of the time.

It was nice chatting with all -TY- Have a good one!

This experiment would show the effects of a rotating Earth.  When the weight is dropped, it would retain the momentum it had, but the ground below it would continue to rotate.  This would cause a very slight deviation, and to an Earth observer it would appear to rotate very very slightly as it fell, if you could measure it accurately.

There are lots of easier ways to demonstrate it, the pendulum and a gyro are two of them. And lots of other evidence. Bullets in flight, artillery shells, laser ring gyroscopes.

Would this one extra experiment prove to you the fact of the Earths spin? 

Re: Question about the Foucault's Pendulum?
« Reply #81 on: June 21, 2020, 09:33:45 AM »
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There are lots of easier ways to demonstrate it, the pendulum and a gyro are two of them. And lots of other evidence. Bullets in flight, artillery shells, laser ring gyroscopes.

Would this one extra experiment prove to you the fact of the Earths spin?

True but just to clear (my) doubt about the direction of the swing which doesn’t change.

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Heiwa

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Re: Question about the Foucault's Pendulum?
« Reply #82 on: June 22, 2020, 07:13:41 AM »
When I lived on the Equator a little north of Mombasa, it was not necessary to use a pendulum to see that Earth is rotating. End March and October the Sun was always rising straight East at 06am out of the Indian Ocean to set a little south behind Kilmanjaro at 06pm. End December and June the Sun rose at 06am little South or North of straight East as the equatorial plane is not lined up with the Sun. We had a grandmother clock with a pendulum lined up North/South so the bob crossed the Equator at regular intervals. When I turned the clock 90° the bob never crossed the Equator. Imagine that.