Foo - Foo MythBusting Thread

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View Full Version : Foo MythBusting Thread


RubenX
02-03-09, 11:08 PM
This is simple, if you know of a myth that could possibly get busted, post it here and suggest some kind of test. If some other Fooster can test it, please do and post the results here. I'll start:

Antigravity fields & Magnets

The myth says that you can create a simple contraption that will create some kind of antigravity field, canceling some of the earth's gravity forces on it. To make the contraption:

1) Get 2 big speaker magnets.
2) Get a screw and some washers and nuts.
3) Use the screw, washers and nuts to force the 2 magnets together, with the repelling poles facing each other (the 2 south or the 2 north).

Now go to a high place and let it fall. Science says that every object falls at the same rate regardless of weight, with an acceleration of 9.8ms^2. The myth says that this antigravity contraption will fall at a measurable slower rate.

Anybody wanna test this? Any other myth you want some other Fooster to test?


cal_gundert05
02-03-09, 11:20 PM
Ha, cool. I don't have a myth to bust, but I just want to say how creepy the Google ads in the OP are--all nuts and screws and stuff. I know I'm a bit late, but I stopped visiting BF shortly after the ads appeared and just came back.

Tex_Arcana
02-03-09, 11:23 PM
What about using those rare earth magnets advertised next to your post?


UnsafeAlpine
02-03-09, 11:27 PM
I don't believe it. I have, however, made an "anti-gravity" machine.

You'll need:

a copper pipe and a pvc pipe both of the same diameter roughly 6 feet long.
two magnets that fit into the pipes.

Copper is great for this, but you should be able to do it with aluminum or some other non-ferrous material.

What you do:

Drop both magnets down the tubes at the same time. Every time you do it, the magnet in the copper pipe will come out slower than the pvc pipe.

Why does this happen:

Copper is non-ferrous meaning it is non-magnetic. The magnet is not slowed by some sort of attraction between the copper and the magnet, so what makes it work?

KrisPistofferson
02-03-09, 11:33 PM
Armor All on the rims makes caliper brakes quit sqeaking.

RubenX
02-03-09, 11:37 PM
Children weight more when sleeping.

Michigander
02-03-09, 11:40 PM
You can plug a bunch of wound up wire into the wall and it will lift off the ground, but heat up very quickly. That's the simplest, but most dangerous method. Youtube has a lot of instructional videos to make safer versions.

Buglady
02-04-09, 12:19 AM
Children weight more when sleeping.

So do cats. It's the damndest thing.

SingingSabre
02-04-09, 12:40 AM
Armor All on the rims makes caliper brakes quit sqeaking.

:lol::lol::lol::lol::lol:

mlts22
02-04-09, 12:53 AM
5 foot high spoilers on Civics make them go faster. Even when the engine isn't running.

AEO
02-04-09, 03:27 AM
pcad goes faster on a cervelo

ehidle
02-04-09, 04:08 AM
Armor All on the rims makes caliper brakes quit working.

De-Mythed it for you...

ehidle
02-04-09, 04:11 AM
Myth: Wearing a Team Discovery kit and riding a Tre..... oh nevermind...

AEO
02-04-09, 04:15 AM
I don't know about you, but my trek team discovery jersey was $20. and I ride cannondale and rossin.

DannoXYZ
02-04-09, 10:08 AM
Why does this happen:

Copper is non-ferrous meaning it is non-magnetic. The magnet is not slowed by some sort of attraction between the copper and the magnet, so what makes it work?A moving magnetic field (falling magnet) will induce an electric current at right-angles to its direction of travel. In this case, around the circumference of the pipe. The moving electric current will then generate a magnetic-field at right-angles to ITS direction of travel. This mag-field will oppose the original mag-field of the falling magnet and resist its movement. However, since we don't have 100% efficient conversion of magnetism-to-electricity-to-magnetism, the generated opposing field is less than the original, thus only slowing the magnet's travel.

In a superconducting scenario, you CAN levitate the magnet... :)

UnsafeAlpine
02-04-09, 10:10 AM
A moving magnetic field (falling magnet) will induce an electric current at right-angles to its direction of travel. In this case, across the circumference of the pipe. A moving electric current will generate a magnetic-field at right-angles to ITS direction of travel. This mag-field will oppose the original mag-field of the falling magnet and resist its movement. However, since we don't have 100% efficient conversion of magnetism-to-electricity-to-magnetism, the generated opposing field is less than the original, thus only slowing the magnet's travel.

In a superconducting scenario, you CAN levitate the magnet... :)

Commonly known as eddy currents. :)

jsharr
02-04-09, 10:17 AM
Chloroform decreases libido

I have been running field tests for a few years now. I guess I need to pull my notes and see.

ehidle
02-04-09, 10:20 AM
A moving magnetic field (falling magnet) will induce an electric current at right-angles to its direction of travel. In this case, around the circumference of the pipe. The moving electric current will then generate a magnetic-field at right-angles to ITS direction of travel. This mag-field will oppose the original mag-field of the falling magnet and resist its movement. However, since we don't have 100% efficient conversion of magnetism-to-electricity-to-magnetism, the generated opposing field is less than the original, thus only slowing the magnet's travel.

In a superconducting scenario, you CAN levitate the magnet... :)

Let me say that far more succinctly...

From my Masters Thesis of old:

http://lh5.ggpht.com/_RX2uz5fR3dA/SMfMn0yauVI/AAAAAAAAE8Q/aqFp_sqZRmI/s720/maxwells.JPG

:p

Wordbiker
02-04-09, 10:25 AM
jsharr is a witch.

Test: Build a bridge out of him.

skinnyone
02-04-09, 03:48 PM
Let me say that far more succinctly...

From my Masters Thesis of old:

http://lh5.ggpht.com/_RX2uz5fR3dA/SMfMn0yauVI/AAAAAAAAE8Q/aqFp_sqZRmI/s720/maxwells.JPG

:p

Dude don't tell me you have one of those t-shirts!

ModoVincere
02-05-09, 08:56 AM
X has brain!
UA uses a brain!

UnsafeAlpine
02-05-09, 09:07 AM
X has brain!
UA uses a brain!

I have to use x's brain... Mine's been melted.