Dynamic reaction versus Coriolis acceleration of the disk

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SUMMARY

The discussion focuses on distinguishing between Dynamic reaction and Coriolis acceleration in a system involving a thin hoop of mass m and radius r, spinning at a constant rate ω1 while being supported by a fork-ended vertical rod rotating at a constant rate ω2. The Coriolis acceleration is calculated using the formula ac = 2ω1ω2r, while the gyroscopic couple acceleration is determined using C = Iω1ω2/r, with an inertia mass of 1 kg. The key issue raised is the doubling of Coriolis acceleration compared to gyroscopic acceleration, attributed to a misunderstanding of the Moment Couple definition, which states that a couple consists of two equal and opposite forces with parallel lines of action.

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  • Knowledge of gyroscopic motion and couples
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  • Learn about Coriolis acceleration and its applications in physics
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MPavsic
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<< Thread moved from the technical forums, so no Homework Help Template is shown >>

I have mind boggling problem, trying to distinguish between Dynamic reaction versus Coriolis acceleration of thin hoop.

Problem: A thin, hoop of mass m and radius r spins at the constant rate ω 1 about an axle held by a fork-ended vertical rod, which rotates at the constant rate ω 2. The mass of spokes and spindle are negligible.

1. Determine Coriolis acceleration of point P at the edge of the hoop, when point P is aligned with vertical axis of the rod.

2. Determine acceleration produced by gyroscopic couple of the hoop on axle held by a fork-ended vertical rod, where support of the axle by the rod equals to radius of point P on each side of the hoop.

To solve Coriolis I am using equation ac = 2 omega1 omega2 *r.

To solve acceleration of gyroscopic couple I am using C = I omega1 omega2 / r, where mass to compute inertia = 1kg.

The question is:

Why is Coriolis acceleration doubled in comparison with gyroscopic acceleration? Both are causing the same effect of force and torque consequentially.

Where do i have problem in my calculations?
 
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MPavsic said:
<< Thread moved from the technical forums, so no Homework Help Template is shown >>

I have mind boggling problem, trying to distinguish between Dynamic reaction versus Coriolis acceleration of thin hoop.

Problem: A thin, hoop of mass m and radius r spins at the constant rate ω 1 about an axle held by a fork-ended vertical rod, which rotates at the constant rate ω 2. The mass of spokes and spindle are negligible.

1. Determine Coriolis acceleration of point P at the edge of the hoop, when point P is aligned with vertical axis of the rod.

2. Determine acceleration produced by gyroscopic couple of the hoop on axle held by a fork-ended vertical rod, where support of the axle by the rod equals to radius of point P on each side of the hoop.

To solve Coriolis I am using equation ac = 2 omega1 omega2 *r.

To solve acceleration of gyroscopic couple I am using C = I omega1 omega2 / r, where mass to compute inertia = 1kg.

The question is:

Why is Coriolis acceleration doubled in comparison with gyroscopic acceleration? Both are causing the same effect of force and torque consequentially.

Where do i have problem in my calculations?

I am working on some calculations for my RC model. Wel
MPavsic said:
<< Thread moved from the technical forums, so no Homework Help Template is shown >>

I have mind boggling problem, trying to distinguish between Dynamic reaction versus Coriolis acceleration of thin hoop.

Problem: A thin, hoop of mass m and radius r spins at the constant rate ω 1 about an axle held by a fork-ended vertical rod, which rotates at the constant rate ω 2. The mass of spokes and spindle are negligible.

1. Determine Coriolis acceleration of point P at the edge of the hoop, when point P is aligned with vertical axis of the rod.

2. Determine acceleration produced by gyroscopic couple of the hoop on axle held by a fork-ended vertical rod, where support of the axle by the rod equals to radius of point P on each side of the hoop.

To solve Coriolis I am using equation ac = 2 omega1 omega2 *r.

To solve acceleration of gyroscopic couple I am using C = I omega1 omega2 / r, where mass to compute inertia = 1kg.

The question is:

Why is Coriolis acceleration doubled in comparison with gyroscopic acceleration? Both are causing the same effect of force and torque consequentially.

Where do i have problem in my calculations?

The main problem was, that I did not understand the Moment Copule which is by definition: "Couple is a system of two forces which are equal in magnitude, opposite in direction and have parallel lines of action."
 
The book claims the answer is that all the magnitudes are the same because "the gravitational force on the penguin is the same". I'm having trouble understanding this. I thought the buoyant force was equal to the weight of the fluid displaced. Weight depends on mass which depends on density. Therefore, due to the differing densities the buoyant force will be different in each case? Is this incorrect?

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