# AP Physics 1: 2.1 Object Interaction and Forces

You may not be able to get Einstein-o the Great at your next birthday party, but you can at least figure out his tricks. Let's find out what the magnitude of gravitational force is between two rocks. ...Sounds like a thrilling party, huh? Really regretting your laser tag or ice skating parties right about now, aren't you?

 AP Physics 1 Object Interaction and Forces Language English Language Science Practice 2 Using math appropriately

### Transcript

00:17

entertainment The opening act of einstein owe the great is

00:21

to create gravity He pulls out two rocks each weighing

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four kilograms and twelve kilograms respectively and places them four

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meters apart huh Expressed in terms of g what is

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the magnitude of gravitational force between the two rocks and

00:38

00:43

this question we need to remember isaac newton's law of

00:45

universal gravitation Sir isaac taught the world that the force

00:49

of gravity is equal to the gravitational constant times the

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product of the masses of the two objects divided by

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the square of the distance between the objects Right So

01:01

the equation looks a little something like this right here

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So now all we're left to do is plug in

01:06

the numbers Well the masses of the two objects are

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four kilograms and twelve kilograms And when we multiply those

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together we get yes Forty eight kilograms The distance between

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the objects is four meters So when we square that

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we get sixteen meters Last thing to do is divide

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forty eight by sixteen which comes out to three making

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a three g The correct answer Remember physics might seem

01:30

like magic sometimes but we can learn to make sense

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of it We don't even have to smoke and door 00:01:35.279 --> [endTime] mirrors Teo