What Causes the Coriolis Effect When Throwing a Ball on a Merry-Go-Round?

AI Thread Summary
The Coriolis effect causes a ball thrown inward on a merry-go-round to follow a curved path due to the rotation of the platform. As the ball is thrown, its speed increases relative to the rotating frame, while its angular momentum is conserved. Observers on the merry-go-round perceive the ball's trajectory as curved, while an external inertial frame would show a straight line. The discussion highlights the complexities of analyzing motion in non-inertial frames, where inertial forces like Coriolis and centrifugal forces must be considered. The conservation of angular momentum in non-inertial frames raises questions about its applicability in such contexts.
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Imagine I stand on a merry-go-round and throw a ball inwards towards the center. The path will make a curve due to the coriolis force. I want to know what explains this.
If the ball is thrown inwards, the velocity of the disk gets slower and slower the lower radius as seen from our frame of reference. This will make the ball faster than the rotation.
But at the same time, the balls angular momentum should also be conserved, and thus that should also make the velocity greater. Do both these things then contribute to the coriolis force?
 
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I thought the path merely appears curved because the merry go round is spinning. Isn't it going in a straight line?
 
Not if you see it from the merry-go-rounds point of view. If you are looking from an inertial frame yes. Thats how I think it is.
 
If you're in the rotating frame and want to explain the weird curved path taken by the ball as you see it, you have to invoke the inertial forces, i.e Coriolis and centrifugal forces. But if you do that and calculate where the ball should go while under the influence of those forces, you should predict the trajectory correctly, in reference to your rotating coordinates.

It just so happens that in the external stationary frame, the calculation is much easier to do, and the trajectory is relatively trivial. If you really want to do it in the rotating frame, however, you can.
 
aaaa202 said:
But at the same time, the balls angular momentum should also be conserved...
Who say that angular momentum should be conserved in a non inertial frame of reference?
 
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