Heiwa's bathroom scale experiment

[alexi_drago]

I think it is now clearly obvious that Heiwa knows exactly what is going on, and he is just playing stupid in order to get lots of attention. He has accomplished his goal in a tremendous way.

He's set himself a difficult task but has been quite successful in making the movement look even more ridiculous.

 

[X]

I've not done this stuff for years so there's probably some mistakes but anyone with any involvement in engineering should have some idea about this.

If you place a 1Kg mass onto a set of scales the mass will exert a force of 9.8N and there will be the equal reactive force exerted in the opposite direction from the scales.

Let's drop the 1Kg mass from 3.7m onto scales.

The time taken to fall 3.7m due to gravity can be found with:

s= u*t + 0.5*a*t*t

we know:
distance traveled (s) is 3.7
initial velocity (u) is 0.0 so we can get rid of u*t
accelearation due to gravity (a) is 9.8

3.7=0.5*9.8*t*t
or
t*t=3.7/(0.5*9.8)=0.7551

t=sqr(0.7551)=0.869 seconds for an initaially stationary object to fall 3.7m

The velocity of the object after that time is:

v=u+at

we know:
initial velocity (u) is 0.0
acceleration (a) is 9.8
time (t) is 0.869

v=9.8*0.869=8.516 m/s

Lets say that when the mass hits the scales it takes 0.1 secs for the mass to actually come to rest (all energy is absorbed through deformation and the mass doesn't bounce off) what is the acceleration of the mass duing that time?

we know:
time (t) is 0.1 secs
initial velocity before impact (u) is 8.516
final velocity after impact (v) is 0.0

a=(v-u)/t

a=(0.0-8.516)/0.1=85.16 m/s/s

And the force required to give that acceleration is found with F=m*a

we know:
mass (m) is 1Kg
acceleration (a) is 85.16

F=1.0*85.15=85.16N

So while a stationary 1Kg mass placed on a scale will exert a force of 9.8N , a similar mass dropped from 3.7m will exert an average force of 85.16N for 0.1 secs.

The time of 0.1 secs for such a collision is probably very generous and should be much lower and give a shorter acceleration time and higher force.

Lessee...

assume upwards is positive direction

impact velocity = -(2gd)]^0.5 = -(2*9.8*3.7)^0.5 = -8.52 m/s

assume impact duration of 1/10 of a second (0.1 s) to come to rest


a = dv/dt = (v_{final[/url] - vinitial)/(duration) = (0- (-8.52))/(0.1) = 85.2 m/s/s (be careful of your units) mass is given as 1 kg Net Force = force of scale + force from gravity = ma + mg = m(a + g) = 1(85.2 + 9.8) = 95 Newtons. don't forget to account for the force of gravity) Or, to put it another way, nearly nine-and-a-half times the force of the 1 kg mass on the scale (and vice-versa) when static. Yes, the weight is the same before and after impact. But the point Heiwa keeps dodging is that his hypothesis (and "experiments") concern what goes on during impact. So, Alexi Drago, aside from the small issue of keeping units and not accounting for gravity* , your calculations look good. * You got the net force required for acceleration, but forgot that the scale will still have to counter gravity loads, too. Don't worry, it's a common mistake. At least, for me it is. :blush:}

 

[ihaunter]

Question: Do we know that Heiwa on this forum is actually the same guy from Heiwa Co.? I recall someone saying the Heiwa Co. guy has put out some truther material, but is this really the same guy?

Whether or not they are one and the same, it is clear that he has no intention of having a serious discussion. That's not necessarily a bad thing, as long as people realize it.

 

[WildCat]

Question: Do we know that Heiwa on this forum is actually the same guy from Heiwa Co.? I recall someone saying the Heiwa Co. guy has put out some truther material, but is this really the same guy?

Whether or not they are one and the same, it is clear that he has no intention of having a serious discussion. That's not necessarily a bad thing, as long as people realize it.

His 9/11 nonsense is actually on the front page of the Heiwa web site.

Something tells me, though, that Heiwa Co. doesn't actually do much business. I've seen 6th graders with web sites better designed than that one.

Oh: http://heiwaco.tripod.com/

It's a tripod site for crying out loud!

 

[JohnG]

His 9/11 nonsense is actually on the front page of the Heiwa web site.

Something tells me, though, that Heiwa Co. doesn't actually do much business. I've seen 6th graders with web sites better designed than that one.

Oh: http://heiwaco.tripod.com/

It's a tripod site for crying out loud!

Come on, that's not fair. That's one slick looking site...





...if we were living in the year 1995.





ZING!

 

[Mel Odious]

I have a question about an assumption made by Alexi Drago and [X] in their calculations.

Both assume a time for the 1 kg weight to come to rest of 0.1 seconds. Using [X]'s figure of 95 N, a uniform upward acceleration would be a=95 m/s^2.

Unless I'm doing it wrong, I calculate that this would allow the weight to descend about 37.5 centimeters before stopping. Am I right? My thinking is that delta-t for this problem should be a lot shorter than 0.1 seconds, because the distance to bring the weight to a stop is so small.

Here's how I worked out the bathroom scale problem. I'm looking at the problem from the perspective of momentum and impulse. Feel free to pick it apart.

m = 1 kg
s = 3.7 meters
g = 9.8 m/s^2

v = square root of (2gh)

v = 8.5 m/s

The momentum of the weight at time of contact:

P(init) = 1 kg * 8.5 m/s = 8.5 kg*m/s (downward)

The final momentum P(final) = 0, so the change in momentum is, of course,

delta-P = 8.5 kg*m/s

which makes the impulse exerted by the scale on the weight 8.5 N*s.

Let's say the weight decelerates uniformly so that the average speed during the collision is 1/2 the initial speed:

v(av) = 4.25 m/s. We will consider a case where the scale compresses a distance of:

delta-s = 3 cm (.03 meters) from the impact. We can use these values to calculate delta-t:

delta-t = delta-s / v(av)
delta-t = .03 meters/4.25 m/s
delta-t = 7 milliseconds (.007 sec)

Average force = impulse/delta-t
Average force = 8.5 N*s / .007 s

Average force on the scale = 1214 N

Or about 123 kilograms.

Anyone see a mistake here?

 

[ElMondoHummus]

You know, I'll give this to Heiwa: He's not abusive or overly derogatory, like too many other truthers. He's actually been rather good humored about his absurdities, sort of taking the role of the fool who's actually happy and well pleased about his foolishness (I guess lunacy is rather fulfilling for some?? ). It's as if we've experienced the Nordic version of Max Photon, minus the self-important illeism.

 

[Hokulele]

You know, I'll give this to Heiwa: He's not abusive or overly derogatory, like too many other truthers.

Oh, he has his moments.

He's actually been rather good humored about his absurdities, sort of taking the role of the fool who's actually happy and well pleased about his foolishness (I guess lunacy is rather fulfilling for some?? ). It's as if we've experienced the Nordic version of Max Photon, minus the self-important illeism.

The bit I do not understand is his claim of putting people on ignore. Most trolls or attention hounds would cease posting long before putting portions of their audience on ignore.

 

[MIKILLINI]

As JREF posters discussing the WTC1 collapse on the Pizza Box Tower thread don't know the difference between weight/mass (kg) and force (N) and moving bodies, let's do a new experiment in the bathroom in this thread and prove Bazant and NIST wrong, i.e. debunk them.

All you need is a bathroom scale! And a bathroom. And a ladder.

Assume you are in the bathroom and step on the scale and that it announces that your weight it 120 kgs (or what ever that is in US - 20 inches)! OK, you are only 160 cms (what is that - 3 lbs?) tall, so you are a small, fat weight, but who cares. Most Americans are overweight.

Actually the scale does not register your weight but the force (via a magic device inside the scale) you apply to the scale - in this case about 1180 N - and then it transforms this force into weight - 120 kgs. Ok, big belly but otherwise quite fit.

So far so good. Now the experiment. You are going to jump on the scale from 3.7 meters height and see, if your weight changes. Of course your bathroom has a high ceiling. Americans have big houses.

OK, get the ladder into the bathroom and step up to the 3.7 m level. Don't knock your head against the ceiling.

Now jump on the scale!! WOSH, BANG!

<Snip>

Are you serious? You believe this is a convincing experiment?

 

[MIKILLINI]

When one engineer implies NIST is off base and the next engineer implies NIST is gospel...

which engineer is full of crap?

I would say the one you believe.

 

[ElMondoHummus]

Oh, he has his moments.

Well, yeah, but compared to other seriously over self-centered, oversensitive truthers, he's been way short of abusive.

The bit I do not understand is his claim of putting people on ignore. Most trolls or attention hounds would cease posting long before putting portions of their audience on ignore.

Well, I think his sense of pomposity simply won't allow that to happen. Although I feel the need to put that in perspective; nothing's as pompous as continually referring to one's own self and one's own statements in a carnival barker's manner. Heiwa's not doing that, thank God.

Just, nobody let him start copying old Max's style. Last thing I need is the broken english, the broken math, and the endless referral to ones self in the 3rd person.

 

[Hokulele]

ElMondoHummus, wise man he.

 

[ElMondoHummus]

I mean, could you imagine?

(*Shudders*)

 

[MIKILLINI]

So nobody managed to do the experiment! To fat to get up 3.7 m on a ladder? Eaten too many pizzas? Didn't dare to jump? Or no bathroom scale or ladder at home? Homeless? Bank took the scale? You are broke? In the street? No bathroom?

<Snip>

This appears to be the reason why you started this thread. You can get a few "digs" into Americans.
As for your experiment:

 

[MIKILLINI]

I mean, could you imagine?

(*Shudders*)

I can imagine, but I'm not going to imagine that one!

 

[Heiwa]

Question: Do we know that Heiwa on this forum is actually the same guy from Heiwa Co.? I recall someone saying the Heiwa Co. guy has put out some truther material, but is this really the same guy?

Whether or not they are one and the same, it is clear that he has no intention of having a serious discussion. That's not necessarily a bad thing, as long as people realize it.

One and the same! I actually analyzed >200 oil tanker collision structural damages in the 1990's to find out what really happened (they were all arrested) in order to improve environmental protection and reduce oil spills at sea. Some of these structural damages involved energy inputs bigger than WTC1.

International bodies (incl. IMO)/laws (incl. Marpol) assumed something about these damages (location, extent, pollution, etc) that I showed was incorrect. And IMO accepted my findings and the Marpol law was modified! Only USA disagreed. My findings were apparently not in accordance with US Clean Water Act that could not be challenged or modified. ????

 

[PhantomWolf]

Heiwa,

You are aware that you will get a very different result if you and a mate push two cars together till their bumbers hit at 0.5 m/s than you would if you both drove at each other at 50km a hour until the front bumbers hit. The reason I ask is because you seem totally unaware that your OP experiment has a wrong conculsion.

Try this one. Get two bricks of equal size, a 2 meter long board, and a pipe. Lay the board over the pipe so it balances, then place a brick on each end, equi-distance from the pipe. You should be able to get it the board to remain balanced cause they are both putting the same amount of force on the board. Now remove one and then drop it onto the end of the board from above the hieght of your shoulder. Does the board return to a balanced state?

Disclaimer: The above experiment should only be done with a helmet and watching out for flying bricks.

 

[bio]

One and the same! I actually analyzed >200 oil tanker collision structural damages in the 1990's to find out what really happened (they were all arrested) in order to improve environmental protection and reduce oil spills at sea. Some of these structural damages involved energy inputs bigger than WTC1.

International bodies (incl. IMO)/laws (incl. Marpol) assumed something about these damages (location, extent, pollution, etc) that I showed was incorrect. And IMO accepted my findings and the Marpol law was modified! Only USA disagreed. My findings were apparently not in accordance with US Clean Water Act that could not be challenged or modified. ????

Is there a difference, between a block, which falls from above down on another block (WTC), and two blocks, which collide at a flate (cars, ships)?

 

[lee5]

Is it April? Cause this can't be for real.

 

[A W Smith]

One and the same! I actually analyzed >200 oil tanker collision structural damages in the 1990's to find out what really happened

Thats a lot of buoys you had to weld up.