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Pure maths, physics, logic (braingames.ru): non-trade-related brain games - page 22

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TheXpert:

It's your fantasy. It can be compressible and incompressible.

And the height is non-zero anyway, i.e. some of the energy has gone into it. And there's already a solution.

I don't know how valid it is if the ball is inhomogeneous, but maybe even that doesn't matter.

It is not a fantasy, but a physical concept of one of the abstractions used in solving real world problems.

Oh, hmm, here's a challenge.

A brick is thrown onto a perfectly elastic spring from a height of one metre. The spring is fixed. All energy transfer occurs only between the brick and the spring.

How high will the brick jump :)

Observe billiard balls. Cue balls are very close to perfectly elastic bodies in their properties.
joo:
Observe billiard balls. Billiard balls are very close to perfectly elastic bodies in their properties.
So go ahead and do an experiment with billiard balls. Tell me the results later.
TheXpert:
So go ahead and do the experience with the cue balls. Tell me the results later.

Take a cue ball and fix it firmly to the table (this is an emulation of the floor on which the ball lies). Place another ball close to the table (emulation of a ball). Now hit the ball with a third ball (emulation of a brick). What happens? That's right, the third ball will bounce and the two balls will stay in place.

When the problem was a special case (a tennis ball) it had a solution. As soon as they removed the specifics, leaving "absolutely elastic ball", the solution was no longer unambiguous.
Everyone go to the pool hall to check!
joo:

Take a cue ball and fix it firmly to the table (this is an emulation of the floor on which the ball lies). Place another ball close to the table (emulation of a ball). Now hit the ball with a third ball (emulation of a brick).

Yeah, that's right.

What happens? Right, the third ball bounces off and the two balls stay in place.

Nah, you can check.
TheXpert:

almost 25 cm, imho.

________________________

A --> BAB

B --> ABA

ABAABA --> B.

ABA --> A.

The first problem is correct. I told you TheXpert is good at physics.

About the second one, I'm not sure yet, I'll check it out.

Mathemat:
Also see the third one about the urns, please.
TheXpert:

Yeah, that's right.

No, you can check.

Of course not. The second ball rolls back slightly towards the bounce of the third. This is a consequence of the fact that real billiard balls are not perfectly Absolutely Elastic and still deform. The problem is Absolutely Elastic.

And it's the ball and the brick, not the balls, that's deliberate - to throw you off your game.


ZS. :)

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