What are causing the cup to fly out?

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In summary, the conversation discusses an experiment where blowing between two cups causes the top one to fly out. The individual explains that the air creates a force that pushes the cup up and out. They also mention trying to verify this by cutting out the bottom of the outer cup, but it did not affect the result. The conversation ends with the individual stating that poking holes in the bottom of paper cups did not prevent the top cup from popping up.
  • #1
moment1337
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Hello. I need some help of understanding what forces are causing one of the cups to fly out of the other one when you blow at it. This video describes the experiment.
 
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  • #2
Mo,
It looks as if the individual is blowing right between a cup and the one just above it.
When you blow, what are you doing to the air?
As a hint, if the air is blown between the top cup and the one underneath, it must be the air creating some kind of force to push the cup up and out.
Can you maybe try to give a some kind of explanation on your own now.

PS. You might understand it better by thinking about it some more, than just reading an explanation.
 
  • #3
I have been doing quite a lot of tests on my own now and has sort of came to the conclusion that air pressure is forming at the bottom of the outher cup and pushes the inner one up. I tried verfiying this by cutting out of the bottom of the outer cup, thinking that this would cause the air to escape underneath. Unfortunately this did not happen to be the case.
 
  • #4
I would have come to the the same conclusion.

By cutting out the bottom of the outer cup, did not the air flow out the bottom or was it not able to.
Tried it myself with poking holes in the bottom of paper cups, and the top cup still wants to pop up.
 
  • #5


Based on the information provided in the video, it appears that the force of air pressure is causing the cup to fly out. When you blow into the small opening between the two cups, you are creating an area of high air pressure inside the cup on your side. This high pressure pushes against the cup on the other side, causing it to move away from the force of the air. This is known as the Bernoulli principle, which states that as the speed of a fluid (in this case, air) increases, its pressure decreases. Therefore, the cup on the other side, which is experiencing lower pressure, is pushed away from the area of higher pressure. Additionally, the shape and design of the cups may also play a role in the force of air pressure and the resulting movement of the cups.
 

What are causing the cup to fly out?

1. What is the physical force that causes the cup to fly out?

The physical force most likely causing the cup to fly out is air pressure. When a person blows on the rim of the cup, they create a region of high air pressure inside the cup, which pushes against the inside of the cup and can cause it to fly out.

2. Can the shape or material of the cup affect its ability to fly out?

Yes, the shape and material of the cup can affect its ability to fly out. A taller and narrower cup may have a stronger reaction to the air pressure, causing it to fly out further. Additionally, a lightweight cup made of thin plastic may be more easily pushed by the air pressure compared to a heavy ceramic cup.

3. Is there a specific angle at which the cup is more likely to fly out?

The angle at which the cup is held may impact its ability to fly out. If the cup is held at a slight angle towards the direction of the person blowing, it may have a stronger reaction to the air pressure and fly out further.

4. How does the force of the person blowing on the cup impact its flight?

The force of the person blowing on the cup can impact its flight by creating a stronger or weaker air pressure inside the cup. The stronger the force, the higher the air pressure and the further the cup may fly out.

5. Is there a way to prevent the cup from flying out?

Yes, the cup can be prevented from flying out by either decreasing the force of the person blowing on it or by increasing the weight of the cup. This can be done by using a heavier cup or by filling the cup with a liquid to add weight.

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