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phyahmad
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Is the reason behind coriolis acceleration is that as you move far from the centre of a rotating frame the tangential velocity increases?
But what do u mean moving tangentially I think in that case your velocity wouldn't be constant so it is always true I thinkOrodruin said:If by "tangential velocity increases" you mean "the tangential velocity of a fixed point in the rotating frame relative to an inertial frame", yes, partially. It describes the Coriolis effect when you move radially. If you move tangentially it is the effect of moving with/against the rotation.
I mean consider a rotating disk it consists of infinite concentric circles so any linear uniform motion will take you from one circle to another so the radius of rotation changes and the tangential speed increasesOrodruin said:Constant in what frame?
Linear uniform motion relative to the noninertial framephyahmad said:I mean consider a rotating disk it consists of infinite concentric circles so any linear uniform motion will take you from one circle to another so the radius of rotation changes and the tangential speed increases
But as I said, this does not explain the part of the Coriolis effect when you move along one of the circles. If you move along a circle in the direction of rotation, you will be pushed outwards by the Coriolis effect. If you move against the direction of rotation, you will be pushed inwards.phyahmad said:I mean consider a rotating disk it consists of infinite concentric circles so any linear uniform motion will take you from one circle to another so the radius of rotation changes and the tangential speed increases
My friend moving along one of the circles means there is acceleration relative to the noninertial frame (centripetal)Orodruin said:But as I said, this does not explain the part of the Coriolis effect when you move along one of the circles. If you move along a circle in the direction of rotation, you will be pushed outwards by the Coriolis effect. If you move against the direction of rotation, you will be pushed inwards.
On a merry-go-round in the night,
Coriolis was shaken with fright.
Despite how he walked,
'Twas like he was stalked,
By some fiend always pushing him right.
https://www.physics.harvard.edu/undergrad/limericks
What is the point of this thread?phyahmad said:My friend moving along one of the circles means there is acceleration relative to the noninertial frame (centripetal)
No. In the rotating frame, there are two non-inertial contributions to the radial force. One is the centrifugal effect, which only depends on the distance from the rotational center, but the Coriolis effect also plays a role if an object is moving along one of the circles as seen in the rotating frame.phyahmad said:My friend moving along one of the circles means there is acceleration relative to the noninertial frame (centripetal)
But the required centripetal force changes when he moves tangentially in the rotating frame, and that modification of the required centripetal force coresponds to the radial Coriolis force.phyahmad said:My friend moving along one of the circles means there is acceleration relative to the noninertial frame (centripetal)
https://www.physicsforums.com/threa...ed-by-tangential-velocity.977984/post-6238568A.T. said:One intuitive way to think about the radial Coriolis force, is as a velocity dependent modification of the centrifugal force. In fact you could order the inertial force terms in a rotating frame by direction, and lump the radial Coriolis force with radial centrifugal force together. But for mathematical and historical reasons we separate them as position dependent term (centrifugal) and a velocity dependent term (Coriolis).
Yes, but to make Newton 2nd Law work in the rotating frame you introduce a inertial centrifugal force that balances the real centripetal force for objects at rest in the rotating frame. But if they move tangentially in the rotating frame, the centripetal force is different and so you need a velocity dependent radial inertial force term to make Newton 2nd work again. That is the radial Coriolis force.phyahmad said:Okay but I thought that if the particle is rotating so it has centripetal acceleration relative to noninertial frame the force here is real not fictitious and thats what I meant
The Maths of the topic are hardly a matter for dispute.PeroK said:What is the point of this thread?
The Coriolis effect is the apparent deflection of moving objects when they are viewed from a rotating reference frame. This phenomenon is caused by the rotation of the Earth and affects the movement of air masses, ocean currents, and even projectiles. In the Northern Hemisphere, objects appear to deflect to the right, while in the Southern Hemisphere, they appear to deflect to the left.
The Coriolis effect plays a crucial role in the formation and behavior of large-scale weather systems. It causes the rotation of cyclones and anticyclones, influencing wind patterns and the distribution of weather phenomena. For example, it contributes to the rotation of hurricanes in the Northern Hemisphere and cyclones in the Southern Hemisphere.
The Coriolis acceleration can be mathematically expressed as \( \mathbf{a}_c = -2\mathbf{\Omega} \times \mathbf{v} \), where \( \mathbf{a}_c \) is the Coriolis acceleration, \( \mathbf{\Omega} \) is the angular velocity vector of the rotating frame (such as the Earth), and \( \mathbf{v} \) is the velocity of the moving object relative to the rotating frame. The cross product indicates that the Coriolis acceleration is perpendicular to both the angular velocity and the object's velocity.
Objects moving in a rotating frame experience Coriolis acceleration due to the non-inertial nature of the frame. In a rotating reference frame, the laws of motion include additional fictitious forces, such as the Coriolis force, to account for the effects of rotation. These fictitious forces arise because the rotating frame is accelerating relative to an inertial frame, causing the apparent deflection of moving objects.
The Coriolis effect significantly impacts aviation and navigation by influencing the trajectory of aircraft and ships. Pilots and navigators must account for the Coriolis effect to accurately plan their routes and ensure they reach their intended destinations. Ignoring the Coriolis effect can result in significant deviations from the planned course, especially over long distances.