Date: Sat Apr 28 14:41:13 2007

Author: Richard Heckathorn

Post:
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Greetings,

=20

You spoke about raising 2 balls and only 2 balls
move out the other side.=20

=20

What if you pull back 3?

=20

What if you pull back 4?

=20

What if you pull one ball back on one side and one
ball back on other side?

=20

What if you pull two balls back on one side and
three on the other side?

=20

Repeat for all other possibilities.

=20

In each condition there is a conservation of
momentum.

=20

What about the conservation of kinetic energy?

=20

My first question is it an elastic or inelastic
collision.

=20

To answer that, pull one ball back and have one
other ball at rest. (hold the other three so they
are out of the way).=20

=20

My observation indicates that it is conserved or
very nearly so.

=20

Thus for both momentum (mv) and kinetic energy
(1/2mv2) to both be conserved, the after must be
conserved.

=20

If you have some old pool balls, make a larger
apparatus out of them. Or you could even use
bowling balls of same mass.

=20

=20

Hope this helps

=20

Dick

=20

=20

Helping teachers who facilitate, motivating
students who learn.

Dick Heckathorn 14665 Pawnee Trail Middleburg
Hts, OH 44130 440-826-0834

www.cvcaroyals.org/~rheckathorn/

Adjunct Physics Teacher - Baldwin Wallace College

Physics is learning how to communicate with ones
environment so that it will talk back.

=20

=20

-----Original Message-----
From: tap-l-owner@lists.ncsu.edu
[mailto:tap-l-owner@lists.ncsu.edu] On Behalf Of
William Beaty
Sent: Saturday, April 28, 2007 2:00 PM
To: tap-l@lists.ncsu.edu

=20

On Sat, 28 Apr 2007, Borislaw Bilash wrote:

=20

> 1] When ball 1 & 2 are lifted and then relased
why do balls 4 & 5 rise

> up, rather than only ball 5 travelling at twice
the speed?

>

> 2] why does ball 3 not move? (not the same
question, as 1)

=20

Pretend that there are small gaps between all the

works the same, which shows that all the
collisions only involve two balls

hitting each other, not two balls hitting a third.
Drop one ball in, and

it hits the next, which moves and hits the next,
etc. Drop two

closely-spaced balls in and think about what
should happen.

=20

so the balls are not

touching each other. Put 1mm gaps between. Then
it goes "zip zip zip"

rather than "clack clack clack."

=20

=20

=20

(((((((((((((((((( ( ( ( ( (O) ) ) ) )
)))))))))))))))))))

William J. Beaty
SCIENCE HOBBYIST website

billb at amasci com
http://amasci.com

EE/programmer/sci-exhibits amateur science,
hobby projects, sci fair

Seattle, WA 425-222-5066 unusual phenomena,
tesla coils, weird sci

=20

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Greetings,

You spoke about raising 2 balls and only 2 balls move out the =
other
side.

What if you pull back 3?

What if you pull back 4?

What if you pull one ball back on one side and one ball back on =
other
side?

What if you pull two balls back on one side and three on the =
other
side?

Repeat for all other possibilities.

In each condition there is a conservation of =
momentum.

What about the conservation of kinetic energy?

My first question is it an elastic or inelastic =
collision.

To answer that, pull one ball back and have one other ball at =
rest. (hold
the other three so they are out of the way).

My observation indicates that it is conserved or very nearly =
so.

Thus for both momentum (mv) and kinetic energy =
(1/2mv2) to
both be conserved, the after must be conserved.

If you have some old pool balls, make a larger apparatus out of =
them.
Or you could even use bowling balls of same mass.

Hope this helps

Dick

Helping teachers who facilitate, motivating =
students who
learn.

Dick Heckathorn 14665 Pawnee Trail
Middleburg Hts, OH 44130 440-826-0834

www.cvcaroyals.org/~rheckathorn/

Adjunct Physics Teacher - Baldwin Wallace =
College

Physics is learning how to communicate with ones environment so =
that it
will talk back.

-----Original Message-----
From: tap-l-owner@lists.ncsu.edu [mailto:tap-l-owner@lists.ncsu.edu] On =
Behalf
Of William Beaty
Sent: Saturday, April 28, 2007 2:00 PM
To: tap-l@lists.ncsu.edu

On Sat, 28 Apr 2007, Borislaw Bilash wrote:

> 1] When ball 1 & 2 are lifted and then relased =
why do
balls 4 & 5 rise

> up, rather than only ball 5 travelling at twice the =
speed?

>

> 2] why does ball 3 not move? (not the same =
question,
as 1)

Pretend that there are small gaps between all the balls. =
The

works the same, which shows that all the collisions only involve =
two
balls

hitting each other, not two balls hitting a third. Drop =
one ball
in, and

it hits the next, which moves and hits the next, etc. Drop =
two

closely-spaced balls in and think about what should =
happen.

Or better yet, modify your actual Newton's Cradle so the balls =
are not

touching each other. Put 1mm gaps between. Then it =
goes
"zip zip zip"

rather than "clack clack clack."

(((((((((((((((((( ( ( ( (
(O) ) ) ) ) =
)))))))))))))))))))

William J.
Beaty &n=
bsp; &nb=
sp;
SCIENCE HOBBYIST website

billb at amasci
com &nbs=
p; =
;
http://amasci.com

EE/programmer/sci-exhibits amateur science, hobby =
projects,
sci fair

Seattle, WA 425-222-5066 unusual =
phenomena,
tesla coils, weird sci

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