Galileo's "falling bodies" experiment re-created at Pisa

Galileo's "falling bodes" experiment re-created at the Leaning Tower of Pisa on May 31, 2009, by physicist Steve Shore of the University of Pisa. Movie by science journalist Dan Falk.

Category:

Science & Technology

Tags:

• IYA
• Galileo
• science
• physics
• Pisa
• gravity
• gravitation
• falling
• free-fall
• experiment
• bodies
• objects
• re-creation
• re-enactment

[danfalkscience]

@HK379: That's right: The earth pulls more strongly on the big one, bit the big one is harder to accelerate because of its larger mass. Neglecting air resistance, they fall at the same rate. The heavier one does more damage when it hits the ground because kinetic energy depends on mass -- the larger the mass, the more kinetic energy.

[danfalkscience]

@cljohnston108: True! If I didn't put this video together in such a hurry, I would have included a snippet from that. Still impressive, all these years later!

[danfalkscience]

@jfuite: Yes indeed. I think many people are surprised to learn that the concept of "inertia" is still, to some extent, mysterious. In Einstein's general relativity, it is presumed that intertial mass and gravitational mass are the same; but so far it just seems to be an empirical fact that they are, rather than something we can "explain" or "prove" in some other way.

[danfalkscience]

A physicist friend has pointed out that what I say about air resistance is not quite correct, because there is a link between speed and the amount of air resistance. Because of this -- and I admit I glossed over this -- the bolwling ball would in fact hit the ground ahead of the volleyball.

But, at least the large and small water bottles fell at the same rate! :)

[danfalkscience]

Thanks, folks!

[uracistbastard]

Galileo's "falling bodies" experiment re-created at Pisa - 23,000 views

Chinese girl on the right - 6,423,086 view

Not ironic at all

[jursamaj]

@insirtusernamehere

marcusaureliooze said that atmospheric friction was unheard of back then. As I said, and you've admitted, it wasn't. They were well aware of it. Whether they had it precisely defined & quantified is irrelevant.

[insirtusernamehere]

@HK379 An object in space will accelerate towards another object because of gravity. On Earth this is about 9.8 meters per second, but if Earth was heavier. So say you jump out of a plane. You might think 20 seconds later you would be going nearly 196 meters per second, but due to air resistance you will go slower. You accelerate towards Earth at 9.8 meters per second, but if you are air resistant, like a parachute, you will accelerate slower and your max rate of descent will be lower.

[insirtusernamehere]

@jursamaj They knew about it, but they didn't really define it or give a reason for it. It's like being taught a concept and not understanding it. You can say when it works and how to use it, but can't you say how it works. They knew about the wind, as they showed through their knowledge of sails, but they didn't know why it worked like that.

[insirtusernamehere]

@marcusaureliooze In my science textbook the Earth includes the different air levels that extend up miles above the Earth's surface. It does not really matter though.

[WeaselWJ]

Good video!

[HK379]

ok . so the land puuls the heavier stronger ... but the heavier is is more hard to pull because of greater inercia ... ???

I dont get it ...

1.if you drop`em in whater , the heavier sinks faster ...right ?

2.how come when it hits the grownd a havier object does more damage than ?

[BOBandJOE4ever]

Science makes my fingers feel tingly!!!!!!

[BOBandJOE4ever]

Science makes my fingers feel tingly!!!!!!