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A.T.
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Not just irrelevant because its small. Irrelevant for the other reasons stated. And also small.Change in pressure said:That make sense,so small so irrelevant...
Not just irrelevant because its small. Irrelevant for the other reasons stated. And also small.Change in pressure said:That make sense,so small so irrelevant...
Note that even if you stopped the Earth's rotation, ballistic projectiles fired east/west from a location not on the equator, would not stay on the same latitude, but deviate towards the equator (regardless if you fire east or west). This is not the Coriolis effect, but simply how orbits work.Change in pressure said:Dont understand why horizontal correction exist even if you shoot directly est to west or west to east,because bullet going on same latitude where Earth has same "speed" ,so from my logic it must have only vertical correction?
Just to be clear, is the orientation of this platter a slice through Earth along the line of latitude, through Earth's center or sitting on the locally flat Earth?jbriggs444 said:If you are anywhere in the northern hemisphere then the Earth is like a phonograph platter that is rotating counter-clockwise.
In my minds eye, a tilted plate is similar enough to a flat plate to be used for illustration purposes. When you want accuracy, you have to add the ##\cos \theta## terms to express the difference quantitatively.russ_watters said:Just to be clear, the orientation of this platter is a slice through Earth along the line of latitude, right? Not a plate sitting flat on the locally flat Earth.
You mean on this?jbriggs444 said:Exactly at the equator, the east-west deflection for a northward shot is precisely zero. Coriolis ignores the component of velocity parallel to the axis of rotation. [Artillery tables may report a slight deflection because an actual artillery shot will have a non-negligible vertical component. You could see a larger correction for indirect/plunging fire and a lower correction for direct/line of sight fire]
However, as the projectile arcs northward and inward toward the axis of rotation, the inward component of the motion results in the eastward deflection that is eventually seen.
I edited this to add an option and reframe as a question...jbriggs444 said:In my minds eye, a tilted plate is similar enough to a flat plate to be used for illustration purposes. When you want accuracy, you have to add the ##\cos \theta## terms to express the difference quantitatively.
If A aims at B, the ball will not reach B.Change in pressure said:first case,cylinder rotate at 50RPM ,men A throw ball to men B,ball will come to men B because man A and B rotate with same speed or ball velocity vector is parallel to axis or rotation.
If air drag is not exist, why would not reach?A.T. said:If A aims at B, the ball will not reach B.
Why would it follow the curvature of the cylinder to meet B at B's new position?Change in pressure said:If air drag is not exist, why would not reach?
Change in pressure said:If it like you say,than you can hower in the air above africa until south america will appear under you,this is nonsense!
If it's in the lower atmosphere, there is certainly the effect of the atmosphere pushing along with the surface of the earth. That's of course important to aircraft, which ride on that atmosphere. But that's not the case with an artillery shell or especially a ballistic missile, which goes nearly into space.Change in pressure said:Air,aircraft, everything what is in Earth gravity field moves with Earth together,..
I wondered about this. A bullet is effected by winds, but those wind velocities are large compared to the average velocity differences we are concerned with here. So the wind of the rotating atmosphere, compared with an artillery shell, can probably be ignored.RPinPA said:If it's in the lower atmosphere, there is certainly the effect of the atmosphere pushing along with the surface of the earth. That's of course important to aircraft, which ride on that atmosphere. But that's not the case with an artillery shell ...
In that case, if we adopt the rotating reference frame there is no immediate Coriolis force because the initial velocity is parallel to the axis. However there is a centrifugal force which gives rise to a radial acceleration. The radial acceleration, in turn gives rise to a radial velocity and an associated Coriolis force. The combination of the two explains the spiral path observed from the rotating frame as the rising projectile flies away from the cylinder.Change in pressure said:You mean on this?
first case,cylinder rotate at 50RPM ,men A throw ball to men B,ball will come to men B because man A and B rotate with same speed or ball velocity vector is parallel to axis or rotation.
[snip drawing of rotating vertical cylinder with man low on cylinder tossing projectile at man standing directly above]
In that case, there is an immediate Coriolis force and corresponding deflection. This is in addition to the centrifugal force that also exists.[snip drawing of rotating vertically oriented cone with man low and far from axis tossing projectile at man standing high and near the axis]
jbriggs444 said:If you are shooting east, the platter in front of you is rotating left/northward. If you are shooting west, the platter in front of you is rotating left/southward. If you are shooting south, the platter in front of you is rotating left/eastward. If you are shooting north, the platter in front of you is rotating left/westward.
In the temperate latitudes, the axis of rotation does not lie parallel to the surface on which you stand. The rotation vector (pointing out of the pole) has a non-zero component in the direction of the local vertical.Change in pressure said:Can explain this left/nortwarth ,left/southward, with some animation or picture?
I don't understud that,I see only vertical correction when shoot est-west ,west-est.
axis of rotation is prependicular to latitude plane,so this platter is not tilted,so ho can horizontal deflection genereted?
I would suggest you learn to apply Newton's Laws of motion in inertial frames. Judging by your cylinder example you have some misconceptions there.Change in pressure said:I don't understud that,I see only vertical correction when shoot est-west ,west-est.
You might want to rethink that one. It's fictitious as well.Delta2 said:To directly answer the question of this thread:
IMO, Coriolis force cannot be classified as real. Real forces are the ones that belong to one of the following four categories
1). Gravitational
Eh what , gravity is fictitious? Maybe according to relativity but not in classical physicsjbriggs444 said:You might want to rethink that one. It's fictitious as well.
kuruman said:Not so impossible. You can still take a hovering helicopter from New York to London but it will take longer to get there.
That fact throws a bit of cold water on the question, no?Delta2 said:Eh what , gravity is fictitious? Maybe according to relativity but not in classical physics
Er sorry I thought we were in the regime of classical physics here, the sub forum of this post is Classical Physics indeed. It is just not the same thing to say gravity is fictitious force (according to GR) as to say Coriolis is fictitious force, different meaning of fictitious I think. But anyway, gravity is considered to be one of the four fundamental forces of the universe in most books and papers for me gravity is a lot more real than Coriolis. Coriolis force is just a mathematical expression disguised as a force, the only thing real about it is the rotation of the system that seems to "generate" it, but a rotating system does not generate Coriolis force in the same way as the curvature of space time generates gravity.jbriggs444 said:That fact throws a bit of cold water on the question, no?
Does it really matter whether gravity is real or an illusion as long as we agree about the experimental results?
Ignoring air resistance the bullet will move on an elliptical orbit in a plane that contains the center of the Earth. So it will obviously not stay above the 40th parallel, because the plane containing the 40th parallel doesn't contain the center of the Earth. Look up on how orbits in an radial gravitational field workChange in pressure said:I shoot on est on 40th parallel,I see only vertical correction,shoot will come a little bit higher,because target appear to move down as Earth rotate...But my shoot do not cross other parallels...
It is the same machinery -- the mathematics of coordinate systems -- that is responsible for coordinate accelerations of free falling objects in arbitrary coordinate systems in general relativity and for the coordinate accelerations in accelerated coordinate systems in classical mechanics.Delta2 said:It is just not the same thing to say gravity is fictitious force (according to GR) as to say Coriolis is fictitious force
but our assumption is that in first 1000m bullet will go in straight line..A.T. said:Ignoring air resistance the bullet will move on an elliptical orbit in a plane that contains the center of the Earth. So it will obviously not stay above the 40th parallel, because the plane containing the 40th parallel doesn't contain the center of the Earth. Look up on how orbits in an radial gravitational field work
If you could jump high enough, you would notice that you don't land in the same place.Jeffery Winkler said:Try the following experiment. Get out of your chair and stand up. Jump vertically up in the air. Did you land in the same place where you were standing before or off to the side because the Earth moved beneath your feet while you were up in the air?
That's a nonsense assumption.Change in pressure said:but our assumption is that in first 1000m bullet will go in straight line..
A.T. said:If you could jump high enough, you would notice that you don't land in the same place.
Are you trying to come to grips with the difference between a bullet tracking a line of latitude versus a great circle versus a straight line?Change in pressure said:but our assumption is that in first 1000m bullet will go in straight line..
Air (and a helicopter pilot who compensates for the wind and for fuel shortages to stay in place relative to the Earth for 100 years).Change in pressure said:Why than ground do not moving under hover helicopter,even if he hover 100years?
Air exist in bullet situation..jbriggs444 said:Air.
And how many bullets do you see hovering in place for 100 years? What point are you trying to make?Change in pressure said:Air exist in bullet situation..
Delta2 said:IMO, Coriolis force cannot be classified as real.
Delta2 said:Real forces are the ones that belong to one of the following four categories
1). Gravitational
2). Electromagnetic
3) Strong Nuclear
4) Weak Nuclear