Science question

[CornField]

A man takes a heavy steel ball to a third story window and drops it (without obstruction) to the ground. It takes the ball 3 seconds to travel from the window to the ground.

Next the man takes the same ball back to the same window. Instead of an unobstructed fall, however, 10 sheets of typing paper have been placed in the path (suspended by clothes pins from either side). The ball still makes the trip to the ground since the paper is not strong enough to stop the fall. The question: Does the ball still make the journey in the same time frame?

If we wet the typing paper, does the ball fall in the same time frame?

(Of course, assuming all other factors are equal -- wind, gravity, and so forth. The only environmental changes are the pieces of paper placed in the path.)

???

[originalpckelly]

1. The paper will slow the ball's descent...

It will slow it's descent temporarily, so technically it will take it longer to reach the ground, than the unobstructed ball. The wet paper will have less force, so the ball won't slow as much. The wet paper will come in as the second fastest/slowest fall.

[Kutjara]

2. Hmmm, interesting question.

My gut answer is that the ball would fall fastest in plain air, slower through wet typing paper and slower still through dry typing paper. Even though the ball rips through the paper, the act of doing so transfers some of its kenetic energy to the paper, slowing the ball. Wet typing paper would absorb less energy before tearing so it would still slow the ball, but not as much as the dry paper.

[Hosnon]

3. My intuition is that it takes longer. The ball must react in an upward direction

in response to breaking the paper (in a downward direction).

My justification is based on a spectrum. Obviously something strong enough to stop the ball increases the time to infinity. Something that breaks but takes time to open fully to allow the ball through increases the time to some degree. Therefore, anything in the way of that ball that was not there before (given the experiment is exactly the same) increases the time required for the ball to fall completely to the ground.

[originalpckelly]

6. Yep, it acts as a force in the opposing direction of the ball's descent...

and since we know that:
force = mass*acceleration
and we know that the mass of the ball will not change
we know that the ball's acceleration will change because of the force.

This means that the ball will fall slower than it would otherwise.

I would assume that the bonds in the wet paper are weaker, so it would have less force and therefore less negative acceleration.

[Botany]

4. one has to assume that the time to "bust through" one piece of paper

causes a "drag" measured in cubic foot pounds per square jewel as a constant


plus or minus Q and Q = *6.023 x 10 to the 23 power


so if the ball was dropped on a tuesday the answer would be Si'

btw

objects fall @ 9.8 meters per second per second squared (except on weekdays)

[hughee99]

5. I may not remember my physics too well, but...

the force of gravity is the downward force, wind resistance (which should be the same whether the paper is there or not, would be the "upward force", not that the ball is going to get anywhere near terminal velocity in a 3 story drop. The amount of downward force it takes to break the hold on the clothes pins have on the paper (or rip the paper) is an additional upward force, so my guess it would take longer, theoretically, since an additional "upward force" is being applied.

[johnaries]

7. The resistance and friction from the paper will slow the ball down,

although it may not be enough to be measurable depending on the device you are using to measure the speed of the ball.

This is a fundamental problem with scientific experimentation, and what Schroedinger's Cat actually addressed.

The results of an experiment are only as accurate as the measuring devices employed and the observations of the scientist performing the experiment.

[LongTomH]

8. In theory, the upward force of the paper would slow the ball......

However, if you performed the experiment, the difference would probably be on the order of milliseconds.

Wait a minute, could we perform the experiment with a Republican on the ground to catch the ball?

Nominations are open!:evilgrin:

[Buzz Clik]

19. Instead of a ball, let's use a javelin.

[Speck Tater]

9. How heavy is "heavy"?

If "heavy" means just barely enough weight to break through the paper then the sheets might slow it down quite a lot. If "heavy" means 143.7 metric tons of depleted uranium then the effect of the sheets of paper would not be measurable.

Also does the ball actually break the sheet of paper, or does it pull it free from the clothes pins and carry it with it to the ground. In that case, a light enough ball would be slowed considerably by the aerodynamic drag of the fluttering sheet of paper it is dragging along. The same piece of paper being dragged to the ground by a falling 1947 Buick Special (Series 40 four door sedan) would, again, not have a measurable effect.

[WinstonSmith4740]

10. Just had to mention

I'm really enjoying reading the answers to this question, but what keeps going through my mind is...
can you just imagine the answers if this question was posted over at freerepublic? (Not that this question could ever cross their minds) I figured they'd range from "Huh?" to "Paper make a ball go slower? You must hate America, you traitor."

[Dead_Parrot]

11. And for bonus points...

...name a building where the 3^rd story windows are 144 feet above the ground... :)

[Esra Star]

12. I don't know the name, but it's the only building three stories tall

on Pluto

[hughee99]

45. Wouldn't the acceleration due to gravity

be different on Pluto, and therefore a mass falling for 3 seconds would cover a different distance?

[sweetheart]

13. The paper turns to energy e=mc2 and makes the ball fall faster

So, these long super-heavy billiard balls that are in this picture, are falling
slower than the billiard balls through paper. Therefore, things fall faster
in the path of most resistance because of special relativity.

[GreenZoneLT]

14. Is this some retarded, BS rhetorical question about the WTC?

Because people who think that building didn't fall because of the planes, the fire and progressively failing trusses really need to be pointed out and laughed at. A lot.

http://www.thebestpageintheuniverse.net/c.cgi?u=911_morons

[Kingshakabobo]

15. It appears to be.....

It has all the 'common sense' ear-marks.


Another experiment(from the 9/11 forum):

(yes, these are meant to represent the towers, the fires and the load of the upper floors)
(this is not a joke)
http://www.democraticunderground.com/discuss/duboard.php?az=show_topic&forum=125&topic_id=56836#56836

[DoYouEverWonder]

17. Too bad not all floors

had trusses.

[Name removed]

18. Deleted message

Message removed by moderator. Click here to review the message board rules.

[Buzz Clik]

21. And where was Nixon the day Kennedy was shot?

[sweetheart]

24. That's long dead

This is being used to start a world war even today and must be challenged like any reichstag burning.

[Buzz Clik]

31. Meh.

A goofy conspiracy is a goofy conspiracy.

[jschurchin]

43. Dallas

but EVERYONE knows that.

[greyl]

37. Astute. nt

[DoYouEverWonder]

16. Yes, it would take a tiny bit longer for the ball to fall through the paper

unless of course the date is Sept 11, 2001. Then the laws of physics no longer apply.

[Buzz Clik]

20. Instead of paper, let's use tinfoil hats.

[sweetheart]

26. instead of inquiry, lets use presumption

and ridicule. The social control mechanism is in place when liberal persons
will self-police each other to maintain the status quo of an unsupportable
story about a building demolition. The emperor has no clothes is not tinfoil
hat, its the largest robbery ever in human history, the cause for war crimes
killings of hundreds thousands, apparently... and covered up for by heard instinct.

[Buzz Clik]

29. A little presumption on your part, sweetheart?

Dozens -- hundreds? -- of architects and engineers with firsthand knowledge of the WTC collapse have no problem with it. Being married to a Professional Engineer of very high standing, I often rub shoulders with some of the giants in the field. For example, we once were discussing this same issue with the owners of one of the country's top construction firms that has built many of the tallest buildings in NYC. Did you know that the WTC contract went to a low bidder who was previously an outsider in the field (that is, limited experience)? Did you know that the plans for the buildings were heavily criticized prior to construction? Did you know that the upper floors were designed such that the failure of the bolts and rivets would lead to the collapse of the floor, but the design was approved because it was deemed that failure of the necessary fraction of these members was highly unlikely? But, that's EXACTLY what happened.

And, finally, did you know that the construction engineers watching the buildings burn predicted their collapse?

Let me guess -- you also believe that the Pentagon was hit by a cruise missile or a bomb inside the building because the hole was too small for a jetliner. Here's a clue: If you launched an empty aluminum cylinder at a concrete wall at 500 mph, what would happen? (HINT: you'd have a hard time finding the aluminum cylinder and the wall would be undamaged). Clue #2: What if you launched a cylinder of liquid at a wall at 500 mph -- what would happen then? (Getting the idea?)

So, excuse me, sweetheart, but I have one helluva lot more knowledge that some guy on a discussion forum who has a bug up his butt about a conspiracy theory.

Loosen the foil, folks, 'cause it cuts off the flow of blood to your brain.

[quickesst]

49. Got links...

sources, etc. for your claims except that "me and my significant other hobnob with the big boys, and that's what they said?"

You said. "So, excuse me, sweetheart, but I have one helluva lot more knowledge that some guy on a discussion forum who has a bug up his butt about a conspiracy theory.":eyes:

I'm glad you believe you have "ONE" helluva lot more knowledge. Well, I hate to burst your bubble, but I can name several people here who have at least TWO HELLUVA LOT MORE KNOWLEDGES THAN YOU DO.:thumbsup: That's three, count'em, THREE!! You must not eat too much. I know I couldn't if I were so full of myself. Thanks.
quickesst

[Ezlivin]

50. Did those dozens -- hundreds? of architects and engineers look at WTC 7?

What did their incredible knowledge inform them about that building? NIST is baffled. FEMA is baffled. Although they "promise" to look into it further. Six years later what have they found?

Bueller? Anyone?

[DoYouEverWonder]

46. How about steel pans with 4 inches of concrete?

n/t

[EstimatedProphet]

22. It would be microseconds longer in this case

[OPERATIONMINDCRIME]

23. Of Course The Resistance, However Slight, Would Alter The Time.

But the real observational question would be "Why is this question relevant to you?"

[sweetheart]

25. probably for this reason:

http://janedoe0911.tripod.com/BilliardBalls.html#c2

[OPERATIONMINDCRIME]

28. I'd Rather See If The OP Has The Courage To Reply Openly Instead Of Via Ridiculous Analogy.

[Buzz Clik]

30. I visited sweetheart's link. A terrible, terrible flaw...

... and right at the beginning.

The entire analysis is based upon the time it takes for the buildings to fall, and the record they are using are seismic. The seismic readings won't begin until the shock of the fall is transmitted to the ground, which will take considerable time to pass through 60+ stories of intact buildings. The building would have been approximately 50% collapsed before the seismic readings commenced.

And all those pretty graphs and detailed analysis. Right in the pisser.

[Hosnon]

33. The time is from the 9/11 Commission Report.

First, I do not believe in the conspiracy...

But, I would hope that the official report would have figured that out and compensated. The analysis states that the official time is roughly 11 seconds. Couldn't the Commission have hired a seismologist to compensate for the time it took the sound waves to travel to the ground?

I mean, they have to do it all of the time: I don't think the seismometer was directly beneath the tower, i.e., they had to compensate for the time it took the sound waves to travel through the ground to the detector.

[Buzz Clik]

35. The 9/11 Report passed along whatever was available.

I'm fairly certain that the commission didn't consider how this information might be used. Certainly, the difference between an 8 second fall versus a 12 second or 15 second fall would be meaningless to them, as it should be.

Had I known that this thread was a trip down Tinfoil Alley, I never would have posted here. The so-called "science" is very reminiscent of the theories presented by those who attempt to discredit evolution.

[CornField]

32. LOL

Ridiculous analogy? Not really -- simple high school physics. But let me respond to the original post with what prompted this.

[OPERATIONMINDCRIME]

34. Yes, Ridiculous Analogy.

Yes, simple high school physics.

No, they don't apply directly to the collapse of the twin towers, if that is in fact what you were alluding to.

[BuyingThyme]

27. If you remove the paper before you drop the ball,

it will fall in the same time frame.

[CornField]

36. Ah well... here's the story anyway

The slowing might be slight -- especially given the parameters of the question as outlined -- but the ball would definitely be slowed by the impacts of the paper, regardless of whether the paper had been weakend prior to the exercise. And, as one poster pointed out, if the ball was forced to drag the paper down, the slowing would increase due to drag and so-forth.

I'm not a scientist at all. I'm a mom who was helping a high school daughter with homework last night with similar questions. (i.e., would a ball bearing rolling down a 30% grade go faster on a wooden plank or on marble? How much time would it take a ball bearing (perfectly smooth) to drop from a certain height under different conditions? What would happen if the ball bearing incountered resistance along the way (such a a tree limb or updrafts or whatever)?

It was actually my daughter, age 15, who posed the above question. I immediately knew what she was getting at and, frankly, I didn't have an answer.

So... if Skinner or Elad is going to ban me for this, I might as well make it worth their while. I have questions and many throughout the world have questions. The laws of physics do not apply to what happened in New York on Sept. 11th. Even if 5-10 seconds are added to the drop time of the towers (to compensate for the lag time in seismic activity or the unknowns of exactly when the fall completed because of being hidden by debris) we still have a situation where, according to basic high school physics, something which should not have happened did happen.

[greyl]

40. Have you, or her, seen Loose Change?

If so, please see the 9-11 Loose Change Second Edition Viewer Guide and this thorough article by Internet Detectives.

[vincent_vega_lives]

41. Here's a simple experiment you can try!

Balance a brick on top of your head. Note how well your skull performs as a brick rest!

Now toss same brick up in the air to of a height of say...10 feet. See how your skull reacts to said bricks impact! What did we learn?

These analogies mean very little and can be manipulated to show what ever you want. :eyes:

[MervinFerd]

47. Sorry, but Basic High School Physics is called Basic for a reason.

Any resistance in the path of a falling object --of course-- slows it -some-. But the amount depends on the quantity of resistance vs the weight of the object. And, where in the fall the resistance is hit. If the resistance is far less than the weight of the object, the slowing may be unmeasurable. And as a post above noted, if a brick hits your head after falling 10 feet, it will have a different effect than if you rest it on your skull.

A more mature answer is this: The collapse of these buildings is of -intense- interest to the people who build and operate very tall buildings--the architects and structural engineers (and implosion specialists) who have spent more years than you have lived in study of structures and their physics and mathematics. There are thousands of such people scattered over the entire Earth. They don't want their existing and new buildings to meet the same fate as the WTC towers.

It is the universal and uncontested opinion of these experts that what happened to the three towers is pretty much exactly what one would expect from the damage sustained.

Your feeling, based on High School Physics and Loose Change is, sorry, not worth the proverbial bucket of warm piss.

[LARED]

51. Things that make you go hummmm

I'm not a scientist at all. .........


The laws of physics do not apply to what happened in New York on Sept. 11th.....


we still have a situation where, according to basic high school physics, something which should not have happened did happen.....

I think I see the problem.

[vincent_vega_lives]

38. WAITAMINUTE

Who let all these strangers in here! This is OUR fucking dungeon! :grr:

[MervinFerd]

48. I presume they followed from the OP.

Bad plan.

[ProfessorGAC]

39. It Slows Down

The static inertia of the paper and the tension of the clothespins need to be overcome before the acceleration due to gravity can resume. Each piece of paper will slightly decelerate the object, giving the next interval a velocity slightly below where it would have been unobstructed.

Inertia always has an effect on the total kinetic energy of a moving body.
The Professor

[jschurchin]

42. No

It will be awfully close to the same time though. Paper does not provide very much resistance to the falling mass of the ball.

[Name removed]

44. Deleted message

Message removed by moderator. Click here to review the message board rules.