WEBVTT - How does gravity work?

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<v Speaker 1>Welcome to brain Stuff from house stuff works dot com

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<v Speaker 1>where smart happens. Hi this Marshal Brain with today's question,

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<v Speaker 1>how does gravity work? Gravity is a common force of nature.

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<v Speaker 1>We experience it constantly every day and take it completely

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<v Speaker 1>for granted. Newton was the first person to study it seriously,

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<v Speaker 1>and he came up with a law of universal gravitation.

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<v Speaker 1>Every object attracts every other object gravitationally. The standard formula

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<v Speaker 1>for gravity is the mass of the first object times

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<v Speaker 1>the mass of the second object times G, also known

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<v Speaker 1>as the gravitational constant over the distance between those two

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<v Speaker 1>objects squared G is an incredibly small number, but it's

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<v Speaker 1>always there between any two masses. That means that if

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<v Speaker 1>you put to one gram objects one centimeter apart from

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<v Speaker 1>one another, they will attract each other with the force

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<v Speaker 1>of G, which is six point six seven times ten

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<v Speaker 1>to the minus eight dines a dying is equal to

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<v Speaker 1>this incredibly small amount of force point o o one

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<v Speaker 1>gram weight, meaning that if you have a dying of

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<v Speaker 1>force available, it can lift point o o one grams

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<v Speaker 1>in Earth's gravitational field. So six point six seven times

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<v Speaker 1>tend to the minus eighth dine is an incredibly minuscule

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<v Speaker 1>force when you deal with massive bodies like the Earth. However,

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<v Speaker 1>that g number actually adds up to be a big thing,

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<v Speaker 1>because Earth has a mass of six times ten to

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<v Speaker 1>That makes for a very powerful force that holds us

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<v Speaker 1>on the planet. Einstein later came along and redefined gravity,

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<v Speaker 1>so there are now two models, Newtonian and Ironsteinian. Ironsteinian

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<v Speaker 1>gravitational theory has features that allow it to predict the

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<v Speaker 1>motion of light around very massive objects and several other

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<v Speaker 1>interesting phenomena if certain assumptions and simplifications are made. Ienstein's

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<v Speaker 1>equations handle Newtonian gravity as a subset. The question of

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<v Speaker 1>why adams attract one another is still not completely understood.

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<v Speaker 1>For more on this and thousands of other topics, is

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<v Speaker 1>As a Netflix member, you can instantly watch TV and

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