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**unzapped** · 03-15-2010, 05:36 PM

Lenz Effect

This is not new or bizarre. This is simply the lenz effect. Google it
UZ

**Aaron** · 03-15-2010, 05:38 PM

counter currents

The magnet induces a current that creates its own magnetic field that
opposes the permanent magnet's field. It is a farily well known effect
demonstrating Lenz's law.

Physics Zone - Lenz's Law

**ewizard** · 03-15-2010, 05:41 PM

I find it very strange to see and experience and have come across Lenz's law in dicussions here but apparently I thought it applied to electric circuits and coils or electromagnets but I was unaware it had anything to do with a simple copper pipe and magnets. If it is a known effect I wonder why Boyd would not explain it as if it was some military secret. I'll take a better look at the Lenz law. It still is an effect that's fun to see and demo.

I just started reading Lenz Law - so far all I see are statements that it relates to electromagnetism and nothing I did had any electric current or coils involved. Still reading....
I just finished reading the Wiki page on Lenz law and I see nothing that applies to this situation. Is there something I'm missing in Lenz law? I'll dig around some more but so far it doesn't seem to have anything to do with this.

**ewizard** · 03-15-2010, 05:49 PM

Okay - Thanks guys - I didn't think about the fact that it's movement would induce a field. Still a really strange effect to experience. That link you gave Aaron makes it clear.

**ewizard** · 03-15-2010, 05:58 PM

One other observation that seems a bit odd now that I am more familiar with how the Lenz law is having an effect here -- in the larger diameter aluminum tube the magnet stack seemed to move even slower. I would think that aluminum being less conductive and a larger diameter would have less effect on the rate of fall.

It also seems a bit strange that there is no effect if you drop the magnets along the outside of the pipe. Although I can see it would not work as well but it seems there would be some slowing.

**ewizard** · 03-15-2010, 06:21 PM

I'm still puzzling over this. Here's a couple more things I tried. I have a piece of Titanium pipe which is also completely non-magnetic to the neo magnets but it is very electrically conductive. It had zero effect - the magnets fell through at a normal rate. Until I check more into this I'll assume that Titanium will not create an induced magnetic field. But I also found that Titanium does not block a magnetic field. Lots of fun learning this - feel like I'm back in school

**ewizard** · 03-15-2010, 07:38 PM

Okay one more test I found interesting and this actually confirms the Lenz Law over what I was finding in the last post. I guess I'm finding this very fascinating and wonder if there aren't some unexplored applications. I found a flat thin strip of aluminum about 2" wide x 1/16" thick by 30" long. I propped it up against a table to where it was almost vertical but with a slight tilt. I put a single neo 3/4" by 1/8" think on the side of the aluminum. I would have expected (before today) that the magnet would go flying down the side rapidly. It slowly moved down the side taking about 6 seconds to reach the bottom. I guess at my age it's fascinating to see these effects that I had never come across before.

**1NRG24Seven** · 03-15-2010, 07:53 PM

Originally posted by ewizard View Post

I find it very strange to see and experience and have come across Lenz's law in dicussions here but apparently I thought it applied to electric circuits and coils or electromagnets but I was unaware it had anything to do with a simple copper pipe and magnets. If it is a known effect I wonder why Boyd would not explain it as if it was some military secret. I'll take a better look at the Lenz law. It still is an effect that's fun to see and demo.

I just started reading Lenz Law - so far all I see are statements that it relates to electromagnetism and nothing I did had any electric current or coils involved. Still reading....
I just finished reading the Wiki page on Lenz law and I see nothing that applies to this situation. Is there something I'm missing in Lenz law? I'll dig around some more but so far it doesn't seem to have anything to do with this.

Now spin the copper pipe at a high rate of speed while standing upright as you drop the magnet through it, It will either stand still of propel it upwards. The use of Aluminum instead of copper might work better, heavy wall of 1/2" to 3/4" wall thickness pipe....24

**Aaron** · 03-15-2010, 08:54 PM

all objects do NOT fall at the same rate

Non-ferrous objects fall slower than ferrous or other objects.

This has been measured in labs with precision equipment.

A falling copper sphere for example will fall slower than an iron sphere
for the same reasons that you're seeing. The earth magnetic field is inducing
the counter currents that repel the copper from its fall, slowing it a bit.

Effect is small but measurable. I have the article somewhere.

**gyula** · 03-15-2010, 09:56 PM

Eddy current

Originally posted by ewizard View Post

I'm still puzzling over this. Here's a couple more things I tried. I have a piece of Titanium pipe which is also completely non-magnetic to the neo magnets but it is very electrically conductive. It had zero effect - the magnets fell through at a normal rate. Until I check more into this I'll assume that Titanium will not create an induced magnetic field. But I also found that Titanium does not block a magnetic field. Lots of fun learning this - feel like I'm back in school

@Ewizard,

If you search on the web for eddy current losses you will find many interesting articles on your present interest.
Because the magnetic fields of the current loops induced in the wall of your pipes while the magnet falls will work AGAINST the fall i.e. against the move that created the field --> Lenz law, and those current loops are caused by eddy currents see also Foucault currents.
The induced eddy currents depend on frequency and the wall thickness of the pipes. I think your Titanium pipe has a much thinner wall than your other pipes that retard the fall. (Just think of transformer laminations, they are precisely were introduced for minimizing eddy current losses in transformers or electric motors.)

Just out of curiosity, take a look at this paper, it deals with eddy current losses in transformer windings, and several properties are discussed that you or someone else may find useful:
http://focus.ti.com/lit/ml/slup197/slup197.pdf

Also, you may wish to repeat your test with a tilt strip but now you cover a piece of wood or hard paper surface with a single layer of common kitchen Alu foil and repeat the Neo magnet fall. You experience the effect of thickness differences.

rgds, Gyula

**ewizard** · 03-16-2010, 12:45 AM

Thanks everyone again for the continuing education on this fascinating phenomenon. I've really been out of any active research for several years and while I have read a lot recently in posts here that mention Lenz's law it is so much more interesting to see it in action.

I found another aluminum pipe later today that was smaller in diameter and very near the same wall thickness as my titanium pipe. A magnet goes very slow through the aluminum but still plops right through the titanium with no slowing action noted. I'm just guessing that titanium does not have any noticeable flux induced by magnets. Being that it is conductive I wonder if that might be useful in some way.

**Freezer** · 03-16-2010, 02:03 AM

I think Boyd Bushman was giving a clue on how he first discovered his anti-gravity effect. He mentions numerous times about the magnet and aluminum, and also the opposing magnet drop which reduced the rate of acceleration. So we have two $5,000 neodymiums in repulsion forced together by a brass bolt, which fell slower than an object of the same weight. Then we have the magnet which has the opposing field within the copper. The secret seems to be how two strong opposing fields interact with gravity.

YouTube - Boyd Bushman on Anti Gravity

Pt.1
YouTube - Boyd Bushman Part 1
Pt.2
YouTube - Boyd Bushman Part 2
Pt.3
YouTube - Boyd Bushman Part 3

**Schpankme** · 03-16-2010, 03:05 AM

Originally posted by gyula View Post

take a look at this paper, it deals with eddy current losses in transformer windings, and several properties are discussed that you or someone else may find useful:
http://focus.ti.com/lit/ml/slup197/slup197.pdf

Unfortunately, the majority of this document is the by product of Einstein-Relativity-Babble in which the author describes Current flowing IN the WIRE and the TIME domain.

Quote:
'The time domain: If a rapidly rising current is applied to the wire, the voltage across the wire is quite large, mostly across Lx. Internal inductance Li blocks the current from the wire interior, forcing it to flow at the surface through the left-most resistance element, even after the current has reached its final value and the voltage across Lx collapses. Although the energy demand of Lx is satisfied, the voltage across the wire is still quite large because current has not penetrated significantly into the wire and must flow through the high resistance of the limited cross-section area at the surface. Additional source energy is then mostly dissipated in the resistance of this surface layer." - Lloyd H. Dixon, Jr.

- Schpankme

**dambit** · 03-16-2010, 05:11 AM

If you stand next to an MRI machine with an aluminium tray while it is on, drop the tray and watch as it slowly falls to the floor. It's pretty trippy to see.

Cheers,

Steve

P.S I do realise that not everyone has an MRI machine at there disposal.

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Bizarre Anti-Gravity effect - Can anyone explain?

Bizarre Anti-Gravity effect - Can anyone explain?

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