Does this paragraph about a falling cup make sense?

In summary: Torque means a twisting force. If you have equal and opposite forces, but in different 'lines of action', the result will be a tendency to twist the object they're acting on.In the case of this cup, as you say, the mass is concentrated towards the bottom, but the drag is not. Just draw a picture of a tilted rectangle with the drag acting upwards in the middle, but gravity acting downwards near the bottom end. Do you see the twisting effect?
  • #1
TheExibo
55
1
A cup with a mass/weight at the bottom was filled with cotton and an egg was place inside for a physics project. As the cup was falling, it would always re position itself to fall with the bottom/heavier half first (the bottom contains the mass). Would it make sense to explain this case this way:

After a test drop with a plastic egg, the plastic cup had tipped over and landed on its side. This issue was resolved by placing a mass at the center of the bottom of a second cup, and placing the first cup on top. Because the bottom half of the device was now heavier, it would be less affected by air drag than the top half, and the egg-helmet would always position itself in mid-air with the heavier half at the bottom. This repositioning was a result of the collision with the cup and all the stationary air molecules in the way. The half with more mass will have more momentum to spare among the air molecules that it encounters, thus maintaining more speed than the lighter half.

Thanks!
 
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  • #2
It's sort of right, but it would be better to explain it in terms of torque. Imagine the cup tilted somewhat while falling. Draw where you think the forces of gravity and drag will act.
 
  • #3
haruspex said:
It's sort of right, but it would be better to explain it in terms of torque. Imagine the cup tilted somewhat while falling. Draw where you think the forces of gravity and drag will act.

How would you explain it using torque? I'm not familiar with what it is.
 
  • #4
TheExibo said:
How would you explain it using torque? I'm not familiar with what it is.
Torque means a twisting force. If you have equal and opposite forces, but in different 'lines of action', the result will be a tendency to twist the object they're acting on.
In the case of this cup, as you say, the mass is concentrated towards the bottom, but the drag is not. Just draw a picture of a tilted rectangle with the drag acting upwards in the middle, but gravity acting downwards near the bottom end. Do you see the twisting effect?
 
  • #5
Yes, this explanation makes sense in the context of a physics project. The addition of a mass at the bottom of the cup would indeed make it less affected by air drag and cause it to fall with the heavier half first. The collision with the cup and air molecules also plays a role in the repositioning of the cup and egg. This experiment demonstrates concepts of momentum and air resistance, which are important in physics.
 

1. What does the paragraph say about the falling cup?

The paragraph describes the motion of a falling cup, including its initial position, acceleration due to gravity, and eventual impact with the ground.

2. Is the paragraph scientifically accurate?

Yes, the paragraph accurately describes the basic principles of the motion of a falling object, such as a cup, in a gravitational field.

3. Are there any missing details in the paragraph?

It is possible that the paragraph could include more specific details, such as the height from which the cup is falling or the material of the cup, to provide a more complete picture of the situation. However, the paragraph is still clear and understandable without these additional details.

4. How does the paragraph relate to other scientific concepts?

The paragraph relates to the concepts of gravity, acceleration, and force, which are fundamental principles in physics. It also demonstrates the application of these concepts to a real-world scenario.

5. Can you provide a visual representation of the described motion?

Yes, a graph or diagram could be created to visually represent the motion described in the paragraph. This could help to further clarify the concepts and make the paragraph easier to understand.

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