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Physics seems super intimidating after all it's an entire [equations surrounding a boy]

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world of complicated formulas and difficult math how are we supposed to

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understand it we're all gonna die before we get too freaked out let's take

00:26

a deep breath ahh how centering now that we have plenty of oxygen we can [lots of students looking puzzled over a physics class]

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actually see that the world of physics isn't actually terrifying it's just

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[boy trying to scare another student in the class] about describing the world we already live in so physics is a science that

00:40

studies motions and forces and those are all over the place in our day-to-day

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lives one of the most important forces gravity it's the force that makes things

00:49

fall to the ground if you've ever dropped water balloons out of a window [woman throwing a water balloon out of a window]

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you owe gravity a thank you card and if you've never been hit by a falling water

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balloon you owe gravity and not cool man card do they make those? [water balloon landing on a boys head]

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another important force we see a lot is friction the force that helps moving objects slow

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down it's what makes the brakes on our bikes work as friction builds between [woman cycling down the side of a road]

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our brakes and the tires our bike gradually comes to a stop which is good

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because as much as we like our bikes we don't think we'd want to ride it forever

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[man crashing as he rides his bike down the road] so thanks we can see how these two forces interact when we consider

01:22

what happens in a sport like ski jumping the skier starts by pushing off from the

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top of a very tall hill or mountain gravity pulls them downwards helping [woman skiing down from the top of the mountain]

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them go faster and faster building up speed when they hit the jump they fly

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up into the air but they come right back down thanks to gravity ski jumping would

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probably be a lot less popular if you had to worry about flying in to space [a ski jumper floating around in outer space]

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every time you did it finally when the skier wants to come to a stop they turn

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their skis into the snow using friction to slow down with all the work they're [skier turning skis into the snow to come to a halt]

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doing it kind of seems like gravity and friction deserve a spot on the podium

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just saying in fact gravity is so important lots of people who build stuff design [woman on top of a podium waving her skis]

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things with gravity in mind that's true whether it's an architect designing a

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building using gravity to keep it stable or rocket scientists designing a rocket [a rocket launching from a launch pad]

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to escape gravity's powerful pull because no one wants their house

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collapsing as soon as it's done or the Rockets hopping up a couple

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of feet then landing back on earth even though it might be kind of cool to live [rocket launching but quickly falling back to earth]

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in a rocketship and now back to that deep breathing

02:24

ahh better

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