Some funny theoretical tasks, classical physics

AI Thread Summary
The discussion revolves around a theoretical physics exercise involving a ball floating in a water-filled cylindrical vessel with air injected from the bottom. Participants analyze how the introduction of air bubbles affects the ball's buoyancy and floating level. One viewpoint suggests that the ball will float higher due to the upward force from rising bubbles, while another emphasizes that the water level itself should not influence the ball's float level. The conversation highlights the complexities of buoyancy and density changes without specific data on pressure or temperature. Overall, the exercise serves as a thought experiment in classical physics principles.
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Good morning!
I want to show you a few exercises given to me by my Physics teacher as an additional task. I'm aware that for some of you they may seem trivial, but I found it hard to face them because of them being full theoretical, with no actual data given. Mind that I'm only 15 :(. I'd love to hear some tips

1) A ball was floating in a water-filled cylindrical vessel. Through evenly spaced small holes at the bottom, air started to be injected. How will the dipping change?(average, not taking the flowing out bubbles into consideration)

My thoughts:
- air dissolves in the water, due that fact the average density of the solution should decrease, in theory. We weren't given the data about the pressure, temperature of the water, we don't know if its saturated
-Do the bubbles have an influence on the ball?This is the first, and probably the easiest exercise. Should you show some interest, I'll give more :P

Sorry if i might sound strange, I'm not native English
 
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Welcome to PF!

So I guess they want to know if the ball float level changes when air is injected into the water.

I think the ball would float higher because it gets buffeted by rising air bubbles that push it upward.
 
Assuming the ball is not pushed up the cylinder by the flow of air...

Initially what happens to the water level as the air is introduced into the bottom of the cylinder?
What happens to the buoyancy of the ball as the small bubbles rise and displace the water around the ball?
 
montoyas7940 said:
Assuming the ball is not pushed up the cylinder by the flow of air...

Initially what happens to the water level as the air is introduced into the bottom of the cylinder?
What happens to the buoyancy of the ball as the small bubbles rise and displace the water around the ball?

The water level itself should not affect the float level in my opinion
 
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