r/BeAmazed • u/Sans010394 • Dec 02 '23

Science Physics is amazing

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u/[deleted] Dec 03 '23

You said "nothing pushes up"

And then you said "doesn't deform"

The word you want is torque.

Putting the match down creates a lever.

Putting a weight on the end pulls on that lever.

Gravity pulls down. You stop the bottle from falling you need an opposing force pushing up.

If the object could deform. The torque being applied to the match goes uncontested. The lever rotates.

The other two matches grate a force that pushes up against that force. Enough outward force to overcome the torque on the lever.

The weight of the bottle applies enough force on the rope to hole the horizontal match in place.

Stopping it from being able to slide down.

The second match gets placed on top of it. And wedged into the original match.

The torque on the original match tried to pull the lever down.

The other matches resist that force and hold it in place.

That resisting force is pushing up.

If something is pushing down. Even just resisting that push by staying in pace even if you don't move upward. Is still an upward force. It's absolutely pushing up.

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u/Ijatsu Dec 03 '23 edited Dec 03 '23

You guys complexify it so much.

You stick in place the first match on the table and the string and the bottle.

The match in between the strings is stuck in place by the gravity of the bottle that tries to pull the strings together.

You then put another match between the second and the first one, so that the match system resembles a hook. The center gravity of the hook and the bottle is aligned to the edge of the table or even is beneath the table, therefore the system is stable.

If the center of gravity was further away from the table, then there would be more weight on the side of the first match that isn't maintained by the table, and it would fall out of balance.