I'm on a roll.....

April 17, 2003

Let the bashing ensue....

Here's a good one:

What would happen if every geocacher worldwide stood on a chair...follow me here....

and jumped off onto the ground at the same exact second.....

Are there enough of us to have an impact whatsoever?

We had a discussion today about this at work, which related to the population of China, and wondered if it was even possible, even with a mass population.

[This message was edited by opey one on April 17, 2003 at 07:09 PM.]

April 17, 2003

quote:
Originally posted by opey one:
Let the bashing ensue....

Here's a good one:

What would happen if every geocacher worldwide stood on a chair...follow me here....

and jumped off onto the ground at the same exact second.....

Are there enough of us to have an impact whatsoever?

We had a discussion today about this at work, which related to the population of China, and wondered if it was even possible, even with a mass population.

They are currently not approving locationless caches. Therefore, since we couldn't log it, well it wouldn't go off very well.

beatnik

2.8k · April 17, 2003

Assuming there is decent distribution of cachers around the globe the forces would cancel.

This is a normal chair right, not barstool height? My knees aren't what they used to be.

April 17, 2003

Hee hee! I'm amazed at how many views with much less replies.

Maybe people are afraid of touching this one.

I recall years ago a comment made (that I really believed), about the great population count in China, and that is what I was referencing earlier.

I took the bait. Seems the vast population density in China would have some effect on the world catastrophically (i.e. disrupting the earth's orbit or the like), if every person were to perform the "jump" at the precise moment. Maybe there's someone to shed a little more light on this one.

Now, the comments are welcome, don't be scared. I'm just a dumb coal miner from SW Virginia.

Not to offend other dummies, coal miners or people from SW Va, but lately this forum has been real critical, so I went ahead and said it first before anyone else had the pleasure (Man, UMC must be sick or working OT).

Now give us some research facts, you intelligent ones! And I do NOT want to hear that someone was blowing up my skirt, either. And for the rest of the smart a$$es, I don't wear a skirt, so chill!

April 17, 2003

quote:
Originally posted by opey one:

I'm just a dumb coal miner from SW Virginia.

We have some agreement here, but I don't believe you're a coal miner. My granpaw was a coal miner from western Kentucky, and he'd never let the cat have any of his smokes.

April 17, 2003

I think it is WAY too dangerous, what if somebody tries to stand on a chair with wheels, that's an accident waiting to happen.

When should we do it?

_________________________________________________________

If trees could scream, would we still cut them down?

Well, maybe if they screamed all the time, for no reason.

Click here for my Geocaching pictures

April 18, 2003

We would probably get 25% of the cachers' in the hospital with sprained ankles or busted knees and someone would then have to maintain their caches for them.

Another 25% would claim a workmans comp claim and so the business world would slow down to a crawl and the dollar stores would have to file for bankruptcy.

The other 50% would spill their beer which would make the brewery stocks shoot thru the roof because of increased demand for their product.

If you fly like an Eagle the Turkeys don't bug you!!!

1k · April 18, 2003

I do remember a story awhile back, not sure if it was in asia or the UK, but a similar test was done with school kids jumping to demonstrate the richter scale or see how high they could score on it. Anyone else remember this?

Kar

TEAM SHIBBY!!!!

Krs, Kar & Na

April 18, 2003

quote:
Originally posted by imeagle:

We would probably get 25% of the cachers' in the hospital with sprained ankles or busted knees and someone would then have to maintain their caches for them.

Another 25% would claim a workmans comp claim and so the business world would slow down to a crawl and the dollar stores would have to file for bankruptcy.

The other 50% would spill their beer which would make the brewery stocks shoot thru the roof because of increased demand for their product.

http://myweb.cableone.net/imeagle/images/Cache/eagle1.jpg

If you fly like an Eagle the Turkeys don't bug you!!!

Of that final 50% who spilled their beer, at least 4 of them would log into the forums to ask if this cache should have been approved, and 8 of them would wonder why they couldn't leave a pocket knife in their chair as a trading item.

April 18, 2003

Good thought Opey One. But where will we find a chair large enough to hold all the geocachers?

I've never been lost, but I was a might bewildered for three days once. Daniel Boone

5k · April 18, 2003

Here's the deal. Jumping off a chair using gravity does not have any affect on you or the Earth. The net force is zero. Through gravity, both you and the Earth are pulled toward one another. That's right. If you climb a chair and jump off, not only do you fall toward the Earth, but Earth falls toward you. Of course, the Earth's movement in this case is immeasurable, but it's there. It's one of Newton's laws.

In any case, simply climbing up onto the chair exerts just as much force on the Earth as jumping off that chair. What if we all climbed onto a chair at the same time? You aren't creating any energy by jumping off the chair. You're simply using energy you stored by climbing it.

What would happen if all the people in China jumped off a chair simultaneously? There might be some localized movement detectable on the Richter scale, as Shibby pointed out, but the Earth wouldn't be knocked out of its orbit or anything. The net force on the earth/human system is zero, and we wouldn't go anywhere.

Only a force outside our earth/human system could have an effect, such as some space debris of some kind.

Jamie

April 18, 2003

Do you think maybe if all the GeoCachers lie on the ground that the world will spin faster?

April 18, 2003

quote:
Originally posted by Jamie Z:
In any case, simply climbing up onto the chair exerts just as much force on the Earth as jumping off that chair. What if we all climbed onto a chair at the same time? You aren't creating any energy by jumping off the chair. You're simply using energy you stored by climbing it.

Jamie

You're confusing energy with force. The force you exert on the earth when climbing into the chair is not the same as when you jump off and hit, since F=ma. You accelerate slowly when climbing, but decelerate fast when you land. To prove this, lay on the floor and have someone stand on you and then climb up onto a chair next to you. Then have that person jump off the chair onto you. Then ask yourself if the forces were equal.

On a more practical note, it would be interesting to see how the "all the people in china" scenario compares to all the force exerted on the earth during all of our rocket launches in florida over the years. Over 100 shuttle launches alone must add up to quite a lot of people jumping up and down.

24.7k · April 18, 2003

What claypigeon58 is saying is that when it's all said and done, and the scientists are done scribbling equations, it's a wash.

=====================

Wherever you go there you are.

April 18, 2003

I believe that this would actually be modeled as a conservation of momentum problem, the good old M1V1=M2V2 approach. We could debate whether the collisions are elastic or inelastic, depends on soil types and shoes. It is further complicated by the gyroscopic motion of the earth and the resultant resistance of the earth to change the orientation of its pole. The dispersion of the jumpers around the globe would factor in also, and there would certainly be some offsetting collisions.

dadgum, I miss school. Time to fire up the HP and crunch numbers. Not.

Claypigeon58 and Renegade Knight are correct - it wouldn't amount to anything material. I'd put my P.E. stamp on that

I've never been lost, but I was a might bewildered for three days once. Daniel Boone[/i

[This message was edited by Geo Strider on April 18, 2003 at 09:40 AM.]

April 18, 2003

Darned double posts.

I've never been lost, but I was a might bewildered for three days once. Daniel Boone

5k · April 18, 2003

quote:
Originally posted by claypigeon58:
F=ma. You accelerate slowly when climbing, but decelerate fast when you land. To prove this, lay on the floor and have someone stand on you and then climb up onto a chair next to you. Then have that person jump off the chair onto you. Then ask yourself if the forces were equal.

I still stand by what I said.

The acceleration of gravity on the earth's surface is 9.8m/s^2, whether I'm climbing a chair or jumping off said chair. Since a person's mass doesn't appreciably vary in the time it takes to climb and jump off a chair, F is the same for both equations.

When you climb the chair, you are exerting a force on the earth. That force is your mass times the acceleration of gravity. When you jump, it's the exact same force, but in the opposite direction. (from the persective of the human)

Jamie

1.3k · April 18, 2003

Well, the cool thing is that timing would be easy, we all have GPS recivers with clocks updated from an atomic clock. So, what happens if we all run due east at the same time, will we exert enough force to make the day shorter?

I think I read somewhere that the entire human population of the world would fit into a cubic mile.

"Searching with my good eye closed"

April 18, 2003

quote:
Originally posted by BloenCustoms:
So, what happens if we all run due east at the same time, will we exert enough force to make the day shorter?

Sure... But when we all stop, it would get longer again...

----------------------------------

"The number you have reached is imaginary, please rotate your phone 90 degrees and try again... <beeeeep>"

1.7k · April 18, 2003

quote:
Originally posted by Jamie Z:
When you climb the chair, you are exerting a force on the earth. That force is your mass times the acceleration of gravity.

Slightly more, at first, since you have to accelerate your fat butt upward, but slightly less at the end as you let gravity slow you back down again. A fun experiment to show this: if you're careful, you can balance on top of two aluminum cans, one for each foot. If you're really careful, you can balance on one aluminum can while standing on one foot. Okay, you're doing that, right? Not touching anything else, are you? Okay, now hop off.

On the average, though, you're basically right (assuming "on the average" actually meant anything; it really doesn't.)

1.7k · April 18, 2003

quote:
Originally posted by Team VE:
"The number you have reached is imaginary, please rotate your phone 90 degrees and try again... <beeeeep>"

When I was in college, that was my outgoing message. One day, a friend of my mother's happened to call. Here's what I heard:

<beeeeep.>

Cindy: Ron, is that you?

<beeeeep.>

Cindy: See, that's what I heard.

Operator: I have no idea what that is, but it's not us.

<beeeeep.>

Cindy: Ron?

<Beeeeep.>

Mom: Ron, I just got a call from Cindy. She's trying to get hold of you. Could you call her at xxx-xxx-xxxx?

April 18, 2003

And here I thought I had stolen it from from an old .sig of a math professor at the University of Heidelberg....

I spent far too much time in complex math in the mid 90's

April 18, 2003

From the bathroom walls (Engineering Building, Institue of Technology, UofMN):

Lim (IT) GPA -->0 = CLA

April 18, 2003

Old computer joke*

Halloween = Christmas

because Oct 31 = Dec 25

*Where joke is used loosely

April 18, 2003

quote:
Originally posted by AllenLacy:
Halloween = Christmas because Oct 31 = Dec 25

Be careful or a witch could put Hex 19 on you....

April 18, 2003

quote:
Originally posted by Jamie Z:

quote:
Originally posted by claypigeon58:
F=ma. You accelerate slowly when climbing, but decelerate fast when you land. To prove this, lay on the floor and have someone stand on you and then climb up onto a chair next to you. Then have that person jump off the chair onto you. Then ask yourself if the forces were equal.

I still stand by what I said.

The acceleration of gravity on the earth's surface is 9.8m/s^2, whether I'm climbing a chair or jumping off said chair. Since a person's mass doesn't appreciably vary in the time it takes to climb and jump off a chair, F is the same for both equations.

When you climb the chair, you are exerting a force on the earth. That force is your mass times the acceleration of gravity. When you jump, it's the exact same force, but in the opposite direction. (from the persective of the human)

Jamie

You're not taking into account one very important fact. True, mass and the gravitational constant don't change, hence yes, you weigh the same going up or down. So the force the earth exerts on you never changes. However, it's the sum of the forces that equals ma, not just the force the earth exerts on you, i.e. your weight. You have to factor in the *reactive* force of your body pushing off the earth and landing on earth again. If you push off gently, you exert a small reactive force at the point your foot touches the ground. The corresponding acceleration that lifts you is small. But if you are falling at a high rate of speed, your deceleration is high. Therefore to satisfy the equation, F (or sum of F) must be just as high. So where does the extra F come from? The reactive force you impart into the earth (or it imparts on you) resulting from velocity going to zero in a very short time. It's the *sum* of the forces = ma, and there's more forces at work here than just your body weight. And like I said before, even if you didn't know the first thing about physics, common sense tells you that climbing a ladder 20 feet and then jumping off the roof results in a greater force when you hit the ground than when you climbed the ladder. I think if try said experiment, you will rethink your statement that the forces are equal (if you're still alive).

April 18, 2003

Conversation of energy has to hold, but your potential energy right before you jump is more than F=ma, it's F=mah (where h is height in meters or feet). The Earth has to push back with that amount of force.

There's that thread about Geocaching being for geeks.......

April 18, 2003

Claypidegeon and Jamie Z,

Sounds like what your guys are really debating is something called "Impulse", which is the change of momemtum over time. It has the same units as force, but is a different physical concept.

I've never been lost, but I was a might bewildered for three days once. Daniel Boone

20.7k · April 18, 2003

quote:
Originally posted by BloenCustoms:...
I think I read somewhere that the entire human population of the world would fit into a cubic mile. ...

Would we all still be human shaped or would it be human puree?

April 18, 2003

Geez ...

This is one of those theoretical problems that can NEVER be demonstrated.

Ignoring Einstein's essay treatment of the difficulty of the concept of simultaneity, even if you could get all the geocachers up on chairs you could never get them to jump off anywhere near the same time. Everybody would be looking at their elevation reading. 1/3 would be wondering why they don't show an elevation change. Another 1/3 will be wondering why their elevation continues to change. The final third will be tempted to disclaim even being a geocacher since they were the only ones that jumped on-time and now look silly.

Faster, Better, Cheaper

Pick any two.

April 18, 2003

quote:
Originally posted by yeahright:
Geez ...

This is one of those theoretical problems that can NEVER be demonstrated.

Ignoring Einstein's essay treatment of the difficulty of the concept of simultaneity, even if you could get all the geocachers up on chairs you could never get them to jump off anywhere near the same time. Everybody would be looking at their elevation reading. 1/3 would be wondering why they don't show an elevation change. Another 1/3 will be wondering why their elevation continues to change. The final third will be tempted to disclaim even being a geocacher since they were the only ones that jumped on-time and now look silly.

Faster, Better, Cheaper

Pick any two.

That's probably the most accurate response, yet! .

Thanks, all for the science and drama lessons!

1.7k · April 18, 2003

Jeez Jamie Z, claypigeon and the rest of you over-my-head physics people, you took all of the fun out of it before I could post a reply. Here goes anyway.

Opey one said:I recall years ago a comment made (that I really believed), about the great population count in China, and that is what I was referencing earlier.

I took the bait. Seems the vast population density in China would have some effect on the world catastrophically (i.e. disrupting the earth's orbit or the like), if every person were to perform the "jump" at the precise moment. Maybe there's someone to shed a little more light on this one.

So is this a new weapon of mass destruction?

Till a voice, as bad as Conscience, rang interminable changes

On one everlasting Whisper day and night repeated -- so:

"Something hidden. Go and find it. Go and look behind the Ranges --

"Something lost behind the Ranges. Lost and waiting for you. Go!"

Rudyard Kipling , The Explorer 1898

April 18, 2003

Bet you didn't expect this college physics lesson when you did the original post.

April 18, 2003

The article jumping chinese on urbanlegends might shed some light.

2.8k · April 18, 2003

quote:
Conversation of energy has to hold, ...

It certainly has in this thread

2.3k · April 18, 2003

Okay...okay...so when are we gonna jump? Pass the word: let's set a time, say next weekend, Saturday the 26th while we are all out cleaning up for CITO, let's jump at exactly noon E.S.T. according to our GPSr's. And you have to be outside. I'll do it. But if California slides into the Pacific, I will deny any and all involvement. I was never here. You don't know me. Innocent, I say. "Geocaching.com, what's THAT?"

[This message was edited by TEAM 360 on April 18, 2003 at 06:24 PM.]

May 15, 2003

Jamie, perhaps you forgot conservation of angular momentum.

A couple of decades back, a girl who was a grad student in Astronomy advised me that it was possible with then current tech to measure the slow-down in Earth's rotation due to sap rising in trees during northern hemisphere spring and speed-up in the fall.

Might not the proposed action have a similar effect?

Dreamer of Pictures

1.1k · May 15, 2003

Here's an answer from Cecil Adams's Straight Dope column:

Straight Dope Archive

May 15, 2003

OK people,,,,

If EVERY SINGLE PERSON ON THE EARTH jumped at once... the Earth would not be effected AT ALL.

Lets think about this,,, take the average weight of a person, multiply it by the Earths population, that # would be MUCH MUCH less weight than the weight of the Earth.

--- I think someone is remembering the days on the school bus, when all 20 or 30 kids jumped to the other side, and scared the crap out of the bus driver.

May 15, 2003

Here's another idea we could try:

Several years ago, a local radio station decided to try to mess with the water supply/pressure in town by having as many people as possible flush their toilets at the same time. They promoted the event for weeks, and gave a countdown so everyone listening could be waiting, fingers on the handle, to flush when the count hit zero. They then had people call and e-mail what they observed.

Some people didn't notice any flushing difference, and some (mainly those in the older neighborhoods) observed a decreased 'flushing ability' from their toilet. The people listening in Europe over the internet, of course, didn't notice anything - guess their efforts weren't concentrated enough.

So how about it? Anyone want to try this with all of our toilets?

----

When in doubt, poke it with a stick.

May 15, 2003

STOP! My brain is beginning to fry.

--CoronaKid

May 17, 2003

quote:
Originally posted by GatoRx:
Here's another idea we could try:

Several years ago, a local radio station decided to try to mess with the water supply/pressure in town by having as many people as possible flush their toilets at the same time.

They do a similar thing at Lowes Motor speedway each year to test their sewer system. It's part of the "highlight" for some of the fans.

1.4k · May 17, 2003

Nerds.

---Real men cache in shorts.

May 17, 2003

Originally posted by Nurse Dave & LKay:
Nerds.

QUOTE]

FWIW..."Nerd": A word coined by Dr Seuss in 1950 in his book "If I ran the zoo".

I'm on a roll.....

Recommended Posts

Link to comment

Link to comment

Link to comment

Link to comment

Link to comment

Link to comment

Link to comment

Link to comment

Link to comment

Link to comment

Link to comment

Link to comment

Link to comment

Link to comment

Link to comment

Link to comment

Link to comment

Link to comment

Link to comment

Link to comment

Link to comment

Link to comment

Link to comment

Link to comment

Link to comment

Link to comment

Link to comment

Link to comment

Link to comment

Link to comment

Link to comment

Link to comment

Link to comment

Link to comment

Link to comment

Link to comment

Link to comment

Link to comment

Link to comment

Link to comment

Link to comment

Link to comment

Link to comment

Link to comment

Join the conversation