JacobsLadder

Time to rethink the Earth's motion?

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As a keen golfer I often wonder why my easterly drives have no noticeable difference in distance to my westerly drives despite a calm day.

Surely the rotation of the earth should affect the distance to a small degree?

With the same principle in mind, one also must wonder why a helicopter can hover in place despite being located above a spinning planet?

I'm not entirely sure how Newton explained this anomaly.

 

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Posted (edited)
7 minutes ago, JacobsLadder said:

As a keen golfer I often wonder why my easterly drives have no noticeable difference in distance to my westerly drives despite a calm day.

Surely the rotation of the earth should affect the distance to a small degree?

With the same principle in mind, one also must wonder why a helicopter can hover in place despite being located above a spinning planet?

I'm not entirely sure how Newton explained this anomaly.

 

No rethinking necessary actually. The copter is in the same FoR as the planet...but hey it's explained much better here........

http://www.physicscentral.com/experiment/askaphysicist/physics-answer.cfm?uid=20110218025229

 

and here......

 

https://www.quora.com/Why-cant-helicopters-just-hover-and-let-the-earth-rotate-beneath-it

Edited by beecee

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From your source:

as soon as the helicopter left the ground, the ground would ZOOM away at up to 1,675 kmh

This is what is wrong.

The helicopter is clearly leaving earth's frame of reference and yet this doesn't happen.That suggests to me that the Earth is not moving.

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4 minutes ago, JacobsLadder said:

From your source:

as soon as the helicopter left the ground, the ground would ZOOM away at up to 1,675 kmh

This is what is wrong.

The helicopter is clearly leaving earth's frame of reference and yet this doesn't happen.That suggests to me that the Earth is not moving.

I suggest you read both articles and stop being so obtuse.  Ever heard of inertia? 

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2 minutes ago, JacobsLadder said:

 

as soon as the helicopter left the ground, the ground would ZOOM away at up to 1,675 kmh

 

The article says "OTHERWISE as soon as the..."    It clearly won't as it is travelling at the same speed as the earth whilst at rest on the surface. So when it takes off it already has the horizontal speed.  

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I'm not being obtuse.

I'm merely pointing out inconsistencies in the accepted laws of motion.

I will read the articles thanks.

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Posted (edited)

Does gravity have anything to do with maintaining your position in the air wrt the Earth as well, being centripetal?

Edited by StringJunky

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Imagine you are on a train speeding along at 200 km/h.

If you start juggling, the balls do not fly towards the back of the train at 200km/h, they just go straight up and down as if you were not moving.

This was pointed out by Galileo some time ago: https://en.wikipedia.org/wiki/Galilean_invariance

The rotating Earth is very slightly more complex as there will be a small sideways force due to the Coriolis effect.

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From the first article:

In order to put the satellite into a specific orbit, they can't just shoot it straight up from the Earth's surface. They have to apply horizontal forces as well, in order to counter the Earth's rotation and get the satellite into the correct orbit.

So why is different for helicopters?

It seems helicopters can go straight up and down but not satellites . Why do these forces not apply to helicopters?

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Posted (edited)
3 minutes ago, JacobsLadder said:

It seems helicopters can go straight up and down but not satellites .

You don't want satellites to go straight up and down! You want them to go into orbit. Which means giving them a large sideways velocity - this is why the launch rockets are so large (it's not to get them up into space).

Edited by Strange

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Posted (edited)
8 minutes ago, Strange said:

Imagine you are on a train speeding along at 200 km/h.

If you start juggling, the balls do not fly towards the back of the train at 200km/h, they just go straight up and down as if you were not moving.

This was pointed out by Galileo some time ago: https://en.wikipedia.org/wiki/Galilean_invariance

The rotating Earth is very slightly more complex as there will be a small sideways force due to the Coriolis effect.

That is my point. The balls go up and down.

That suggests the earth is stationary.

Edited by JacobsLadder

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11 minutes ago, JacobsLadder said:

I'm not being obtuse.

I'm merely pointing out inconsistencies in the accepted laws of motion.

I will read the articles thanks.

The only inconsistencies are in your  incorrect  interpretation and knowledge or lack thereof, of basic physics.

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Just now, JacobsLadder said:

That suggests the earth is stationary.

It shows that it can be considered to be stationary, just as you can consider the train to be stationary when moving along with it.

There is no sense in which you can say that the Earth or the train IS stationary. All motion is defined relative to something.

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1 minute ago, JacobsLadder said:

That is my point. The balls go up and down.

That suggests the earth is stationary.

The balls are moving at the same speed as the train, in the same direction, with respect to the ground. Why would that motion cease as soon as the balls are tossed in the air?

Speed is always with respect to something, and physics works in any inertial (i.e. non-accelerating) frame of reference.

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So why doesn't my golf shot go into space?

If it has inertia in one direction surely it should keep travelling out of the atmosphere.

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Posted (edited)
3 minutes ago, swansont said:

physics works in any inertial (i.e. non-accelerating) frame of reference.

I guess we should say, "physics works the same way in any inertial FoR" ! (Not that physics doesn't work on non-inertial frames)

Just now, JacobsLadder said:

So why doesn't my golf shot go into space?

If it has inertia in one direction surely it should keep travelling out of the atmosphere.

Remember Newton's laws of motion? It will continue moving in the same direction unless acted on by a force. In this case there is the force of gravity and air resistance. This will bring it back down to Earth.

Edited by Strange

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Yes, so it should be the same in both directions.

If there is rotation at 1,675 kmh then the wind would be way beyond hurricane force.

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5 minutes ago, Strange said:

I guess we should say, "physics works the same way in any inertial FoR" ! (Not that physics doesn't work on non-inertial frames)

Yes. The same equations are relevant in inertial frames. In non-inertial frames, you have to modify the equations.

Just now, JacobsLadder said:

Yes, so it should be the same in both directions.

If there is rotation at 1,675 kmh then the wind would be way beyond hurricane force.

The air moves along with the earth. It's the relative motion that matters. 

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The problem with that is that it is a rotational movement.

It is not linear, therefore we would expect to see anything in earth's atmosphere being ejected into space by the wind.

 

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15 minutes ago, Strange said:

It shows that it can be considered to be stationary, just as you can consider the train to be stationary when moving along with it.

There is no sense in which you can say that the Earth or the train IS stationary. All motion is defined relative to something.

Relativity is a genius theory, but remember strange it only describes possibilities of reality.

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3 minutes ago, JacobsLadder said:

That doesn't explain the inertia.

No - but it explains why the ball doesn't go flying off into space because of inertia like you said it should.  The ball is going in a straight line (tangential to the earth) and would keep going (off into space as you suggested) if a centripetal force wasn't applied to it. This force is applied to it via gravity.

 

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6 minutes ago, Scotty99 said:

Relativity is a genius theory, but remember strange it only describes possibilities of reality.

And those possibilities have been confirmed by experiment. So it appears to describe the reality we live in.

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I can't say I am convinced.

I tend towards Occam's razor in this case.

I have yet to see a convincing argument that the earth is in motion although I appreciate your feedback.

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