Moment of inertia and angular acceleration

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Doubling the fall height of a mass attached to a wheel affects its angular acceleration. The discussion highlights that angular acceleration is related to the energy conservation principle and kinematic equations for rotating bodies. It suggests that with increased height, the final speed of the mass increases, potentially leading to a doubling of angular acceleration. However, the relationship between fall distance and acceleration needs careful consideration, particularly if the mass were free to fall. Overall, the conclusion drawn is that the angular acceleration likely doubles with the increased height.
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Homework Statement


If the fall height of the mass is doubled, the angular acceleration of the wheel will
a. decrease by an unkown amount
b. remain unchanged
c. decrease by a factor of 2
d. increase by an unknown amount
e. increase by a factor of 2


Homework Equations





The Attempt at a Solution


well since angular acceleration is slope of linear graph and if we double the height(x-axis) I think the angular frequency will remain constant. But maybe I'm wrong. That is why I need help.
 
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If the fall height of the mass is doubled, the angular acceleration of the wheel will
The description is not complete.
Fall of what and how is this related to a wheel?

Is this a mass falls onto a wheel, where it stays somehow, and so makes it turn?
Hint: conservation of energy.
 
its a suspended mass attached to to the hub of a bicycle wheel through a pulley. so basically we release the wheel (which is attached to a table) and it turns from the weight of the suspended mass until the mass reaches the floor.
Anyways I have come to a new conclusion that the angular acceleration doubles from the height being double.
I still need confirmation though.
 
Yeh - the final speed is higher, but the time is also longer.
You need to use the kinematic equations for rotating bodies or conservation of energy if you want a mathematical approach - or you can use your understanding of gravity.

If the mass were free to just fall - not attached to the wheel - how would the acceleration be affected by the distance it has to fall?
 
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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