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sophiecentaur

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Yes, the explanation you have given is sufficient to explain the effect. Angular Momentum does not add anything to the analysis. The analysis could be expressed differently, using angular momentum instead of Newton's equations, but that would be anIs a kinematic consideration sufficient to explain completely the Coriolis effect in this case?

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Thanks for your answers! Would anyone be so kind as to give some further explanations about how angular momentum affects this phenomenon (deflection of free falling object as seen from Earth)? I get confused between the kinematic explanation and the conservation of angular momentum one, maybe this would help to make things clearer. Thanks in advice for your help.Yes, the explanation you have given is sufficient to explain the effect. Angular Momentum does not add anything to the analysis. The analysis could be expressed differently, using angular momentum instead of Newton's equations, but that would be analternativeexplanation, not a necessary additional explanation.

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sophiecentaur

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The angular momentum of the object is ##I\omega## where ##I=mr^2## is its moment of inertia about the Earth's rotation axis, ##r## is the object's distance from the rotation axis and ##\omega## is its angular velocity of rotation around the world. Conservation of angular momentum says that this amount, which is ##mr^2\omega##, must remain constant, in the absence of an applied torque. As the object falls, ##r## reduces, so ##\omega## has to increase to compensate, which causes the angular acceleration of the object Eastwards. It's a bit like when a spinning skater has their arms out and then brings them in close, thereby increasing their rate of spin.Would anyone be so kind as to give some further explanations about how angular momentum affects this phenomenon (deflection of free falling object as seen from Earth)? I get confused between the kinematic explanation and the conservation of angular momentum one, maybe this would help to make things clearer.

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The angular momentum of the object is ##I\omega## where ##I=mr^2## is its moment of inertia about the Earth's rotation axis, ##r## is the object's distance from the rotation axis and ##\omega## is its angular velocity of rotation around the world. Conservation of angular momentum says that this amount, which is ##mr^2\omega##, must remain constant, in the absence of an applied torque. As the object falls, ##r## reduces, so ##\omega## has to increase to compensate, which causes the angular acceleration of the object Eastwards. It's a bit like when a spinning skater has their arms out and then brings them in close, thereby increasing their rate of spin.

Thanks so much! It's here my confusion: before, just looking at kinematics considerations we said that the velocity of the object is greater than the one of a point on the Earth, and that's why it seems to be deflected,

Angular momentum is conserved "with respect to" a steady inertial frame, right? Because in Earth system the point at height ##h##, before falling has zero angular momentum, so its angular momentum does not keep constant in Earth system. Nevertheless, as you showed, since ##r## gets smaller the velocity of the object must increase.

Isn't this in contrast with what I said before (i.e. the tangential velocity of the object stays constant while falling)? In other words, in a steady inertial reference frame, is the (tangential) velocity of the object increased when it almost reached the ground, or not?

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That's not quite right. The tangential velocity is ##\omega r##. Since the angular momentum of ##m\omega r^2## is constant, that means that the tangential velocity of the falling object is proportional to ##1/r##. So the tangential velocity also increases as the object falls, but not as fast as the angular velocity increases.The tangential velocity of the object stays constant while falling, if observed in a steady inertial reference.

So we conclude that the answer to this question

is Yes.In other words, in a steady inertial reference frame, is the (tangential) velocity of the object increased when it almost reached the ground, or not?

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