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What will happen to the balance:
micromass said:What will happen
D H said:Way to go Zeta!
There apparently are a lot of people here who think they can pick themselves up by their bootstraps.
BobKat said:It boils down to this question: Does the upward force caused by the air inside the ping pong ball counterbalance the added weight of the ping pong ball itself and the string which holds it. Both balls displace the same amount of water (presumably) and the ball on the right adds no weight to the right side. I suspect the scale stays even, because the air lifts the ball and string - BUT the string is attached to the bottom of the glass, so I don't think it can lift the glass by its own bootstrap (string).
BobKat said:Guess I don't understand how the steel ball contributes the weight of its volume in water to the weight on the right...
BobKat said:Guess I don't understand how the steel ball contributes the weight of its volume in water to the weight on the right...
"easiest to think of it..."? I did not understand one word of what you said. And their weights (including the balls in them) are not the same.chingel said:I think it is easiest to think of it in terms of external forces on the containers, since their weights are the same. The pressure of the water depends only the the height of the water level, which is the same for both of them, but the left container has an additional string pulling it up.
I think we have to be careful not to say that the steel ball's weight somehow channels through the water, because the water pressure is the same in both containers.
Gerinski said:"easiest to think of it..."? I did not understand one word of what you said. And their weights (including the balls in them) are not the same.
The buoyant force on each ball is the same. Buoyant force depends only on the volume of fluid displaced, not the mass of the ball itself.derek10 said:I still don't get it:
Why does the steel ball have buoyancy and the ping pong one doesn't? is it because the steel one is more massive than the other?
(BTW I though than the balance would lean to the left due to the extra weight of the ping pong ball)
Doc Al said:The buoyant force on each ball is the same. Buoyant force depends only on the volume of fluid displaced, not the mass of the ball itself.
Extra weight of the ping pong ball?
That was my first idea too. And it seems like the simplest argument so far to me.chingel said:Water pressure on both of the containers is exactly the same everywhere, but the left container has an extra string attached to it pulling it up, therefore it will go up.
You have two identical steel balls hanging on opposite sides of a scale like this:
You have two buckets, one with water and one with glycerin, standing on opposite sides of a scale like this:
Both scales are initially balanced. Then you fully submerge the balls into the buckets without touching the walls.
Does the balance of the scales change? If yes, how?
A.T. said:Here is a similar one:
I don't thing that's correct, the string in the left container is not pulling it up, as someone said "nobody can lift himself by pulling his bootstraps".chingel said:View the container itself as a system, viewing everything inside and outside of it as external. The containers themselves are the same, they weigh the same. Water pressure on both of the containers is exactly the same everywhere, but the left container has an extra string attached to it pulling it up, therefore it will go up.
As both balls have the same volume and are completely submerged, they both have the same upward buoyant force.Gerinski said:I see the buoyancy argument but as Derek I do not see why only the right side should have the weight of the steel ball's buoyancy and not the left side the same buoyancy by the volume of water displaced by the ping-pong ball.
The balls are held in some fully submerged position, not just dropped and resting on the bottom. So other forces are involved.derek10 said:No it won't change, both sides of the scale have the same mass/weight
Thats the first thing I thought so I'm pretty sure I'm wrong :tongue:
Doc Al said:The balls are held in some fully submerged position, not just dropped and resting on the bottom. So other forces are involved.
Gerinski said:I don't thing that's correct, the string in the left container is not pulling it up, as someone said "nobody can lift himself by pulling his bootstraps".
I see the buoyancy argument but as Derek I do not see why only the right side should have the weight of the steel ball's buoyancy and not the left side the same buoyancy by the volume of water displaced by the ping-pong ball.
That's weird to hear from you as one of your previous posts says:Doc Al said:As both balls have the same volume and are completely submerged, they both have the same upward buoyant force.
The "Physics Riddle: The Fate of the Balance" is a thought experiment that challenges the concept of balance and equilibrium in physics. It involves a scenario where two objects of different masses are placed on opposite ends of a seesaw and asks what would happen if one object suddenly disappeared.
This riddle relates to physics because it explores the principles of balance, equilibrium, and the laws of motion. It also requires critical thinking and problem-solving skills, which are essential in the field of physics.
One possible solution to the riddle is that the seesaw would remain in its original position if the objects have equal masses. However, if the objects have different masses, the seesaw would tilt towards the heavier object due to the force of gravity.
While this riddle may seem like a simple thought experiment, it has real-life applications in various fields such as engineering, architecture, and even sports. It highlights the importance of balance and stability in designing structures and equipment.
As a physicist, this riddle teaches us to think critically and creatively when faced with complex problems. It also reinforces the fundamental principles of physics, such as the laws of motion and the concept of equilibrium. Additionally, it shows the importance of considering all factors and variables in a system when making predictions or solving problems.