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  • - [Voiceover] I could imagine

  • that even the earliest human beings,

  • or possibly pre-human beings

  • had asked themselves the questions,

  • "Why am I here? What is the nature of reality?

  • "Why is the universe organized the way that it is?"

  • And these questions are what we attempt to answer

  • in the field of physics...

  • In the field of physics,

  • which you could view

  • maybe right after mathematics

  • as the purest of the sciences.

  • So you have math, which is very pure,

  • and then on that foundation of math

  • you have physics.

  • And physics really does try to use that mathematics

  • along with some core ideas

  • to explain the phenomena,

  • all the phenomena,

  • of the universe.

  • And physicists will the the first to admit

  • that they are just beginning to understand

  • the nature of reality,

  • the nature of everything around us.

  • Now a lot of times, we think physics

  • is only limited to things like cosmological phenomena

  • or getting rockets into space,

  • or how waves move or building structures.

  • But physics is the foundation for

  • all of the other sciences.

  • When we think about chemistry,

  • when we think about chemistry,

  • which is at the end of the day

  • interactions between atoms,

  • those interactions are really physics-based interactions.

  • So chemistry, chemistry is actually laid down

  • on a foundation of physics.

  • And then even when we think about ourselves,

  • our bodies, even our consciousness, our brains,

  • it really all boils down to chemistry and physics.

  • It boils down to interactions between atoms

  • and even mechanical properties of our bodies.

  • And so even biology,

  • even what we are,

  • is built on a foundation of chemistry.

  • So this is biology right over here,

  • which is built on a foundation of physics,

  • which is highly dependent on some of the math

  • that you've been learning your whole life

  • and that you will continue to learn.

  • And that fundamental question that you might have said,

  • "Well you know, hey, why am I learning this math?"

  • Well one, 'cause the math is beautiful,

  • but also you will see that it starts to,

  • in almost the most pure way,

  • describe the structure of the universe.

  • And we're going to see that more and more and more

  • as we go into physics.

  • All of this complex phenomena

  • that you see around us,

  • whether we're looking at a galaxy

  • or we're looking at ocean waves,

  • or we're looking at even biological systems,

  • we'll see that a shocking amount of them

  • can start to be described using some fairly elegant

  • mathematics that we can build on

  • and continue to build on.

  • Simple or elegant mathematics

  • like force is equal to mass times acceleration.

  • And we're gonna talk about force and acceleration

  • as vector quantities.

  • We're gonna think about things like displacement,

  • and I'll put it as a vector quantity,

  • and we'll soon learn more about vector

  • and scalar quantities are.

  • Displacement is equal to velocity times time.

  • We'll learn things like accelaration

  • is equal to change in velocity over change in time.

  • What we'll see with even a handful

  • of very simple ideas like this.

  • We'll go into much more depth in future videos.

  • You can explain all sorts of complex phenomena.

  • And the one thing that I always loved about physics,

  • and I don't think it's always fully appreciated,

  • sometimes as you start to learn physics,

  • you'll see all these complicated formula,

  • all of these kind of complicated problems,

  • but it's super valuable to realize

  • it's all coming from some of these basic ideas.

  • Some of the things that I just mentioned,

  • these ideas, we're gonna explore ideas of energy.

  • We're going to explore Newton's laws.

  • We're going to explain, we're gonna think about

  • what are the the different types of forces out there,

  • and why they might, why they might actually exist.

  • At its essence, it's all about trying to

  • explain the complexity of the universe,

  • predict what is going to happen

  • based on simple ideas.

  • And that's what physics is all about.

  • Now when we think of physics,

  • it's been studied by humanity for a very, very long time.

  • In fact, I'm sure we don't know

  • who the first physicists were.

  • But some of the,

  • I guess you could say foundational thinkers

  • in physics are these gentlemen that I have here.

  • And this is just a...

  • You could kind of say

  • this is some of the most prominent thinkers in physics,

  • but this is by no means a complete list.

  • First and foremost, we'd wanna include Isaac Newton.

  • Especially when you start to study physics,

  • you're starting to understand the world

  • as Newton understood it.

  • He understood, "Hey, you know,

  • "things don't fall to the ground

  • "just 'cause they always fall to,

  • "just 'cause that's the way the universe is.

  • "That's a force that's acting on it,

  • "and maybe that same force that's causing me

  • "to be stuck to my chair right now

  • "is what keeps Earth orbiting around the Sun

  • "or the moon orbiting around the Earth."

  • He developed Law of Gravitation,

  • Newton's Laws, and we're going to study that

  • as we delve into our basic physics.

  • And what we'll see,

  • even classical mechanics,

  • the physics that Newton established,

  • can explain a large range of phenomena

  • with amazing precision.

  • But as we get into the early 20th century,

  • physics starts to get even more wild

  • as we start to look at the scales

  • of the super small,

  • and we have Max Planck giving us quantum mechanics,

  • and then we have Albert Einstein

  • as we start thinking about super fast speeds,

  • the speed of light, and we realize that's an absolute.

  • That nothing can travel faster than the speed of light,

  • which is this mind-boggling thing

  • that we have these notions

  • of general and special relativity,

  • and we start realizing that the universe

  • is in some ways more bizarre, and more mysterious,

  • and more fascinating than we ever could have imagined.

  • But all of the work, even to understand the modern physics

  • of Max Planck and Albert Einstein,

  • it's based on a lot of the core ideas

  • that were given to us by Isaac Newton,

  • even people before Isaac Newton.

  • So as you go into your study of physics,

  • and I'm kind of a physicist wannabe.

  • I wanted to be a physicist.

  • I imagined kind of,

  • 'cause it's all about, we all wonder,

  • why are we here?

  • What is the nature of reality?

  • Why do things happen the way they are?

  • And these are the questions that physics

  • is attempting to answer.

  • And so as you go into your study of physics,

  • I wanna leave you with some quotes

  • from these three gentlemen.

  • So the first two are from Isaac Newton.

  • "Truth is ever to be found in simplicity,

  • "and not in the multiplicity and the confusion of things."

  • And I really wanted to stress this,

  • because a lot of times in your studies,

  • you might be finding yourself memorizing formulas

  • and vocabulary, but that's,