Galileo's Measure Of Gravity Explained By Jim Al-Khalili | The Amazing World Of Gravity

When you drop an object it's actually quite hard to tell if it falls at a constant speed or picks up speed as it drops, but Galileo realised this...
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[@user-uz9hh3js4u]

Thanks for putting videos like this in the internet. Very useful to show my students at school how the experiment was done historically.

[@cheekiblin690]

I wonder how many ramps Galileo had to build before he could effectively measure acceleration, crazy to think how easy it is in modern times to set this experiment up, while it probably took Galileo a few nights to perfect it! Galileo was a brilliant physicist and astronomer!

[@Styyy]

Thank you so much for Galileo

[@JLar-bb5hl]

What a "genious" - found out that an object increases its speed!! This is density vs. air. Nothing to do with the fantasy called "gravity". buoyancy is another factor.

[@canuckprogressive.3435]

@@JLar-bb5hl There is no bouyancy without gravity.

[@canuckprogressive.3435]

@@JLar-bb5hl It works in a vaccum too.

[@marcineren112]

Mr. Jim this was very inspiring thank you for demonstration :)

[@sanikadixit9223]

Really great efforts for demonstration 👍

[@BillAnt]

The best demonstration is after 40-50 years of age, gravity just grabs your face and starts pulling it down, drooping it.... trust me! ;)

[@urbinamdm]

what a beautiful demostration with bells... really loved it!!

[@Aristothink]

Wonderful experiment you recreated. Amazing. So much work. And it was worth it every second of it. Thank you so much for giving life to Galileo experiments once again. Physics is so amazing..... 🏆

[@pspmemes3588]

Sir ji your experiment is glorious ☺️, due to you ,I understod the Galileo experiment ,thank you So much Sir ji 😊🙏🙏🙏🙏💐💛💛💛💛💛💛💛💛💛💛

[@FermionPhysics]

simply inspiring

[@lincolnthinking]

very nice demonstration ~

[@littlelutz510]

Great Video!

[@technicalcare4293]

amazing explanation

[@ricardocesardasilvagomes9549]

Espetacular!

[@sadbrunorocha]

I think the contact collision with the bell would've slowed the ball down a little bit, but awesome video!

[@syedmuhamedbasheers4959]

when the ball hits the bell i hear the sound and i love science nothing to say

[@hamzasafdar2802]

Nice 👍👌

[@usbreakingnews7880]

Beautiful

[@asadkanasiro3579]

Sir i am discovering a new theory of gravity do the tile also break in vacuum ? This question is very important for my research if you will reply we will see the world with new look

[@user-fj9gc3bt3w]

Yes the tile do break in vacuum

[@davidrandell2224]

“The Final Theory: Rethinking Our Scientific Legacy “,Mark McCutcheon.

[@mowmaster88]

Happy birthday Jim. Thank you for your contribution to my knowledge 🙏.

[@aaax9410]

Galileo is a legend 💯

[@pasquino0733]

Did Galileo's use of bells and water as a measurement derive in any way from musical experiments made by his father Vincenzo Galileo? We know in his late 20s he assisted his father on these experiments. Bells and glasses of water as a measurement reminds me of Pythagorean demonstrations for sound.

[@mcxx8522]

Even if you kept the bells at odd intervals, it might be some amount of resistance to the ball which is travelling on the steep and the results may also not be accurate.

[@jigarbhatiya3329]

What about force on tile ? Even we drop ball at different level of Height ??

[@tombrunila2695]

And Galileo neither had nor needed AI! He used NI, Natural Intelligence!

[@klarageder7372]

Yes

[@wildeysparanormalplace]

New friend here we meet just today but you got an absolute interesting channel I love this so glad to meet you and You got my attention.My name is Myriam a woman from the Netherlands and I always have trouble to get all the information because the language problem but this I very good to fallowing thank for that✌⁉️from Wildeys

[@Make_Boxing_Great_Again]

Two trains, A and B. A weights 100 tonnes and b weighs 10,000 tonnes. Both have the same power to weight ratio, which train accelerates faster?

[@paul30silver]

U just answered your question by saying they both have same ratio to weight

[@Make_Boxing_Great_Again]

@@paul30silver Then you are essentially saying that power to weight ratio is the only variant that determines acceleration performance...

[@paul30silver]

@@Make_Boxing_Great_Again power to weight ratio according to the weight load of each trains over all weight?

[@Make_Boxing_Great_Again]

@@paul30silver Two trains, train A is lighter but with less power. Train B is heavier but with more power. Both of them have the same power to weight ratio as measured by total weight to power (not just cargo weight to power). How will their acceleration performance differ if at all?

[@paul30silver]

@@Make_Boxing_Great_Again I get it but don’t think it is dissected enough but it sounds like a lighter train would accelerate quicker - is it downhill??? 😂 I’m just tripping!

[@infrareddiamonds]

Isn’t it more like 1/2 times the square of distance per time? And because on earth g = 9.81 so multiply that by 9.81?

[@infrareddiamonds]

Oh wait, an acceleration of 1 m/s^2 would travel at 1/2 the square of distance per time while on earth an object will travel 9.81 times 1/2 the square of distance per time which equals 4.905 times the square of distance per time, right?

[@karthik_6938]

ok heres the thing right galileo found out tha t s is proportional to time sqaure(from the experiment we just found) therefore s = kt^2 to remove the proportional sign. He later found out the constant k as 4.9(idk how) giving s=4.9t^2 and with second derivatives of s(t) we found out acceleration to be 9.8m/s^2

[@ProsperousSubconscious]

There appears to be flaws in the methodoligy. As a fixed container of water drains the flow is not constant. To get a reliable result between multiple experiments, the container must be refilled in order to give a consistent measurement. This is only a theory, hypothetically proveable by individual experimentation.

[@Erilsont]

😂thanks for pointing that out.

[@Mordecai0]

I'll tell Galileo right away!!

[@samrader2759]

Sir galalio...❤️

[@erinbaggarly900]

Your denying that the ball rolls faster as it declines or just that the ball is round.

[@trikooCreates]

I find this a little bit misleading because if we follow what you said this will lead the ball to speed up to infinity, but it won't happen because of the air resistance it will reach a point where it stops accelerating and will continue on a constant speed.

[@canuckprogressive.3435]

Well yes, eventualy it would reach a terminal velocity. Air resistance is negligable for the duration of the experiment.

[@mjcruiser4238]

This Galileo fellow -pretty smart

[@heismyrefuge1027]

How is it not that the object has more weight and density than air and it gains speed because there isn’t enough force from the air around it to slow it down?

[@piordas9728]

It’s gravity

[@timetraveler7]

Weight is gravity...

[@goerizal1]

it seems mr. al khalili has great cochlear inner hair cells.

[@ArticPolarBear_]

it was ok

[@ingilizcehazrlk9134]

Galile o_o__o____o________o

[@haniellopez7807]

There goes a gallon of water😅

[@paul30silver]

Using the water in a keg it’s not going to work properly or accurately. The first glass is going to fill quicker due to its maximized weight and pressure falling out hole You would have to refill level to the same amount for each test roll! Anyone disagree???

[@Autovetus]

Last "dings" not timed. ☹️

[@rytrusministry]

Stop misleading people no such thing as Gravity

[@timetraveler7]

There is.

[@wolfinogaming6387]

i feel sorry for u. Not everyone has brain :(

[@Sir_Isaac_Newton_]

I hate that you guys think this was a good demonstration when the angle of elevation of the ramp plays a MAJOR role in the experiment yet isn't mentioned.

[@paullawtable]

Flawed experiment. The water pressure in the barrel was reducing for each ball.

[@tlermanda]

You must feel very smart by pointing out Galileo's experiment is flawed, considering it's 400 years old. It's obvious it has flaws, nevertheless it is a beautiful experiment.

[@paullawtable]

@@tlermanda Yes I am obviously a lot smarter than some people. I was only meaning that the recreation of the experiment was flawed. I feel sure that Galileo knew what he was doing.

[@TomHendricksMusea]

Galileo proved ANTI gravity was the force. The wood ball and iron ball are different weights, but they land exactly the same time. The force from space is the same on both weights, the force from space underneath is the same on both weights. That suggests weight doesn't matter here. Space expanding causes what we've been calling gravity. Space expanding is dark energy or anti gravity. Let's take a second example. The iron weight is ten times larger than the wood weight. They still reach the ground at the same time. Why? The larger iron weight has more space pushing above it, but it also has more space pushing from below it. Both weights have proportional forces pushing against them from up and down, and land at the same time. The astronaut that dropped a hammer and a feather on the moon at the same time proved Galileo correct when they landed at the same time. There is support for anti gravity. The big bang explosion started anti gravity / dark energy. The idea of inflation of the universe supports anti gravity / dark energy. The vacuum energy that pervades the universe supports anti gravity / dark energy. Finally the discovery of the mysterious dark energy supports antigravity / dark energy. But the main physics basis for gravity is common sense! There is more of my ideas connected to this, in other posts.

[@timetraveler7]

Objects fall to the ground at the same time because they're following time like geodesics, when something deviates from this geodesic it experiences a force such as thrust, lift, normal force or bouyance. Objects fall at the same rate due to geometry, not anti gravity, one way to imagine this is grabbing a ball, and drawing two lines from the equator to the north or aouh pole, these two lines converge due to the spheres geometry, gravity is effectively that, but instead of spherical geometry we follow something called schwartzchild geometry. Another simpler reason is that gravitational mass and inertial mass are exactly the same, however this isn't as concise as the geometric definition.

[@krispewkrem3]

Or just use a fucking timer. The fuck?

[@TomHendricksMusea]

Gravity = Acceleration? Does the Earth PULL the APPLE to the ground or Does the Sky PUSH the APPLE to the ground? Which is correct: GRAVITY is pulling matter together or ANTI GRAVITY, another name for DARK ENERGY, is pushing it together? Which is correct: GRAVITY, is inside MATTER somewhere, or ANTI GRAVITY is outside everywhere in empty SPACE? DARK ENERGY in physics is defined as a repulsive force that counteracts gravity and causes the universe to expand everywhere at an accelerating rate. My suggestion is that DARK ENERGY is ANTI GRAVITY. Most likely it is ZERO POINT ENERGY, The COSMOLOGICAL CONSTANT and VIRTUAL PARTICLES too. My next suggestion is that THERE IS NO GRAVITY! My idea is similar to a universe wide CASIMIR EFFECT on all matter. Here, instead of two metal plates being pushed together, there are "plates" of matter and the expanding space around them, pushing them together. Dr Einstein said his breakthrough came when he imagined an analogy of an elevator in space. As acceleration increases, gravity increases. The person in the elevator can't tell if he is in an elevator traveling in space or one on Earth. BUT WHAT IF WE ARE BOTH RIGHT. Look at the drawing. There are two round elevators. The elevator on the left IS NOT accelerating. No acceleration = No gravity The force of empty space or anti gravity, pushes on all sides equally. The elevator on the right IS accelerating. Acceleration = Gravity. The force of empty space or anti gravity, pushes on all sides, but mostly from the front due to acceleration! The acceleration scrunches up the forces in front. They overlap each other from the elevator accelerating into them. These cumulative, empty space, forces, push back more and more as the elevator accelerates in that forward direction. This causes gravity. Acceleration = Gravity! More exactly the forces of ANTI GRAVITY cause matter to experience what we call gravity. So: acceleration of an object in space causes space to push back. This is what we have been calling gravity but is anti gravity. Some will say: But it's so obvious, the Sun goes around the Earth, and the apple falls to the ground. Yes they seem obvious. But both are wrong! My previous posts, part of a single paper covering all these ideas, suggested that before the Big Bang, there was a singularity of photons, an eternal dimensionless point of energy. Then the force that expanded out of the Big Bang and started the universe, and time space, was DARK ENERGY; a subset of the singularity of photons. So Gravity from stars and planets was never PULLING matter together. The opposite was true: Anti Gravity or DARK ENERGY from empty space was expanding and PUSHING matter together from all sides! THERE IS NO GRAVITY pulling anything together. THERE IS ONLY ANTI GRAVITY or DARK ENERGY expanding and pushing matter on all sides. This can explain acceleration in elevators, rocket propulsion; the rubber sheet analogy, why no light escapes black holes, space expansion, curvature of space, and why there is so little gravity in the quantum world. ... Three Follow Ups. 1. Remember the rubber sheet analogy? The rubber sheet is space pushing on all sides. That's the force I'm talking about that causes what we call gravity. Q. The implication is clear (or at least, it was clear to Einstein): Gravity causes acceleration, and acceleration causes gravity. They are absolutely identical 2. Galileo's experiment, later recreated on the moon shows a hammer and feather dropping and hitting the ground at the same time. This supports space pushing them , not the attraction of their weight. 3. Doppler Effect: Waves emitted by a source traveling towards an observer get compressed. 4. The greatest force in the universe is dark energy, the energy of empty space. Dark energy is 70% of all energy. It has such force that its expanding the universe everywhere all the time, and is now speeding up. 5. Dark matter suggests that we need a different theory of gravity. Dark energy or anti gravity would explain both as the force from empty space pushing matter forward, and the force in front of matter resisting its acceleration and giving it mass. 6. The Alan Guth idea of Inflation suggests that the expansion of the universe was driven by an anti gravity force.

[@timetraveler7]

Well thats fine and dandy and all but if you don't have the math or experimentation to back it up it's just conjecture.

[@TomHendricksMusea]

@@timetraveler7 Newton's inverse square law for gravity works just as well in reverse for antigravity. Example, The force on both Earth and Moon from empty space, is anti gravity or dark energy. That antigravity force is the same everywhere with one exception. That exception is the area between the Earth and Moon. That is where antigravity is weakest. The empty space that pushes from all sides, pushes Earth and the Moon together. That antigravity from space is much stronger than the small anti gravity in between the Earth and Moon that barely keeps them apart. Mass is harder to expand than empty space. The force of gravity from mass is really antigravity from empty space.

[@timetraveler7]

@@TomHendricksMusea do you have any sources to back this up? How does this account for relativistic,effects such as gravitational lensing and time dilation?