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Speaker 1: Streaming TV shows and movies directly to your home is

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Speaker 1: Welcome to brain Stuff from house stuff works dot com

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

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Speaker 1: how does gravity work? Gravity is a common force of nature.

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Speaker 1: We experience it constantly every day and take it completely

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Speaker 1: for granted. Newton was the first person to study it seriously,

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Speaker 1: and he came up with a law of universal gravitation.

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Speaker 1: Every object attracts every other object gravitationally. The standard formula

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Speaker 1: for gravity is the mass of the first object times

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Speaker 1: the mass of the second object times G, also known

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Speaker 1: as the gravitational constant over the distance between those two

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Speaker 1: objects squared G is an incredibly small number, but it's

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Speaker 1: always there between any two masses. That means that if

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Speaker 1: you put to one gram objects one centimeter apart from

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Speaker 1: one another, they will attract each other with the force

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Speaker 1: of G, which is six point six seven times ten

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Speaker 1: to the minus eight dines a dying is equal to

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Speaker 1: this incredibly small amount of force point o o one

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Speaker 1: gram weight, meaning that if you have a dying of

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Speaker 1: force available, it can lift point o o one grams

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Speaker 1: in Earth's gravitational field. So six point six seven times

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Speaker 1: tend to the minus eighth dine is an incredibly minuscule

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Speaker 1: force when you deal with massive bodies like the Earth. However,

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Speaker 1: that g number actually adds up to be a big thing,

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Speaker 1: because Earth has a mass of six times ten to

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Speaker 1: That makes for a very powerful force that holds us

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Speaker 1: on the planet. Einstein later came along and redefined gravity,

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Speaker 1: so there are now two models, Newtonian and Ironsteinian. Ironsteinian

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Speaker 1: gravitational theory has features that allow it to predict the

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Speaker 1: motion of light around very massive objects and several other

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Speaker 1: interesting phenomena if certain assumptions and simplifications are made. Ienstein's

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Speaker 1: equations handle Newtonian gravity as a subset. The question of

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Speaker 1: why adams attract one another is still not completely understood.

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Speaker 1: For more on this and thousands of other topics, is

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Speaker 1: it How staff works? Dot com? Streaming TV shows and

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Speaker 1: movies directly to your home is a breeze. With Netflix.

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Speaker 1: As a Netflix member, you can instantly watch TV and

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Speaker 1: movies on your PC, mac, mobile device, or television. Get

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Speaker 1: a free thirty day trial membership. Go to Netflix dot

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Speaker 1: com slash stuff and sign up today.