Re: The mechanism behind bouncing...

On Sun, 04 Feb 2007 20:35:31 GMT, "Jon Slaughter"
<Jon_Slaughter@xxxxxxxxxxx> wrote:


"John Fields" <jfields@xxxxxxxxxxxxxxxxxxxxx> wrote in message
news:fr4cs21bmjbj0l0p4dq9mtr4cpn757i09t@xxxxxxxxxx
On Sun, 04 Feb 2007 14:25:19 GMT, "Jon Slaughter"
<Jon_Slaughter@xxxxxxxxxxx> wrote:

Its a matter of degree.

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Of course. Have you ever seen how a set of contacts is made?

Usually one contact is flat and the other rounded (or they're both
rounded) so that when they're in contact with each other only a
very small area of metal is involved in making the contact.


That way, when the contacts bounce and microscopic welds are made
between the contacts, the spring will have the strength to break the
welds and open the contacts.
---


Yes, but this is explained in a microscopic way.

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And you object to that, why?
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If the contact interface was completely "fused" then thee would
not be any contact interface(assuming the same material is used for both
contacts).

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It doesn't make any difference if the metals are dissimilar or not,
at the weld there is no "interface".
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Sure it does.

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No, it doesn't. If the metals are welded together, then there is no
interface. Even the dissimilar metals will only have a small region
where one diffused into the other and an alloy was formed.
---

This is due to the crystal structure of metals. You don't have this if the
metals are different.

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Bull***. There will be no interface if the molten metals are
capable of dissolving into each other.
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Not sure wha tyour getting at:

It is not, however, a fundamental force, as it originates from the
electromagnetic forces and exchange force between atoms.

The key is originates. It means that it can be "explained" in terms of the
fundamental forces(which there are only 4 so essentially everything can be
explained in terms of that).

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You were claiming that it was a fundamental force. It is not.
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So are you saying there is some other forces involved?

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Nope, but I'm talking at the macro level where when two materials
are pressed together more and more tightly it becomes more and more
difficult to slide them past each other.
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Yes, but how can you even talk about that? You act like the macroscopic
level is something totally different some the microscopic. The macroscopic
is just a manifestation of the microscopic. If you want to talk in those
terms then thats fine. But then we are talking about different things.
Although since the macroscopic is derived from the large scale microscopic
my ideas should, if correct, explain the macroscopic in a much more detailed
way.

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Why do you persist in the idiocy of preaching to the choir?

What the OP was asking about was what caused a counter to miscount
when clocked by a noisy set of contacts, and all you keep doing is
parroting your four-force crap, which is totally irrelevant from the
POV of having the OP understand why contact bounce causes miscounts.

It's as if he'd asked how much charge would flow in a circuit
comprising a resistance of one ohm being driven by a one volt source
and your parroting endlessly that all that matters is electrons
repel each other.
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Sure, but we are not talking about high level.

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I am, because that's all that's needed to describe contact bounce in
response to the OP's question.
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Well, here we have to disagree. Since the OP talked about the microscopic
effect of "friction"(and by the wiki page is the EM and interatomic forces)
then I assumed he ment at the microscopic level.

---
Well, there's microscopic and then there's microscopic.
My belief is that he was talking microscopic at the level of minute
hills and valleys on a metal surface, and metal masses physically
colliding with and repelling each other, which would be consistent
with the generation of the high-level electrical signals required to
clock the counter.

Your bringing up the four fundamental forces and applying them to
the problem incorrectly not only didn't answer the OP's question,
they added considerable confusion to the "discussion".
---

From here one doesn't even have to do any estimation. If there are only 4
forces in the physical world then any macroscopic forces must be derived
from these 4. Friction is not a fundamental force. It is based on the
interactions of a huge number of atoms and the 4 forces. Mechanical
"bounce" is not due to some macroscopic force(although we can use an average
to get it) but only due to the 4 forces. I don't see how you can conclude
anything else. I am not saying that we cannot talk about some derived force
because its almost necessary. What I am saying, now atleast, is that
everything in the physical world is due to these 4 forces(assuming they are
the correct). Any force that you claim is "fundamental" better be one of
these 4 forces and if its not then you better prove it(atleast make enough
of a convincing argument so that it is accepted as a new fundamental force).

If you want to talk about friction or bounce or whatever and ignore the fact
that they exist only because of these 4 forces then you are doing yourself a
disservice. You might get along just fine with beliving that but your no
different than those who thought the world was flat or that the thunder god
was angry at them.

---
You're either grasping at straws or your reading comprehension is
very poor, or both.

I never stated that the four fundamental forces don't exist or that
they're not responsible for our universe being the way it is; what I
stated was that in order to give the OP an answer which was relevant
to his question there was no need to muddy the water by bringing up
the four forces.

As a matter of fact, your claim that an electric field around the
contacts was attracting/repelling them and causing the bounce was
100% off the mark.


--
JF
.

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