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Gases are everywhere, and this is good news and bad news for chemists. The good news: when they are behaving themselves, it's extremely easy to describe their behavior theoretically, experimentally, and mathematically. The bad news is they almost never behave themselves.
In this episode of Crash Course Chemistry, Hank tells how the work of some amazing thinkers combined to produce the Ideal Gas Law, how none of those people were Robert Boyle, and how the ideal gas equation allows you to find out pressure, volume, temperature, or number of moles. You'll also get a quick introduction to a few jargon-y phrases to help you sound like you know what you're talking about.
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Table of Contents
Ideal Gas Law Equation 0:50
Everyone But Robert Boyle 1:35
Ideal Gas Law to Figure Out Things 6:16
Jargon Fun Time 7:46
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In which John Green teaches you about the Indus Valley Civilization, one of the largest of the ancient civilizations. John teaches you the who, how, when, where, and why of the Indus Valley Civilization, and dispenses advice on how to be more successful in your romantic relationships.
Chapters:
Introduction: Why Do We Study History? 00:00
What Does 'Civilization' Mean? 0:54
Characteristics of a Civilization 1:52
The Indus Valley Civilization 3:03
An Open Letter to Historians 5:57
What Happened to the Indus Valley Civilization? 6:52
Credits 9:00
Additional Resources:
Empires of the Indus - https://goo.gl/NoYqkY
Lots of Indus Valley Civ. photos - https://goo.gl/lo9ehY
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Babies have to learn a lot of language stuff before they can even say their first word. Exposure to language as infants doesn’t just help us say those first words but gives us the tools we need to acquire advanced language skills and learn more languages later on in life. In this episode of Crash Course Linguistics, we’ll learn about language acquisition and how the process differs for babies and adults.
Want even more linguistics? Check out the Lingthusiasm podcast, hosted by the writers of Crash Course Linguistics: https://lingthusiasm.com/
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Before we dive into the big questions of philosophy, you need to know how to argue properly. We’ll start with an overview of philosophical reasoning and breakdown of how deductive arguments work (and sometimes don’t work).
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What is culture? How do we define it and how does it change? We’ll explore different categories of culture, like low culture, high culture, and sub-cultures. We'll also revisit our founding theories to consider both a structural functionalist and a conflict theory perspective on what cultures mean for society.
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Today we're going to talk about a fundamental part of all modern computers. The thing that basically everything else uses - the Arithmetic and Logic Unit (or the ALU). The ALU may not have to most exciting name, but it is the mathematical brain of a computer and is responsible for all the calculations your computer does! And it's actually not that complicated. So today we're going to use the binary and logic gates we learned in previous episodes to build one from scratch, and then we'll use our newly minted ALU when we construct the heart of a computer, the CPU, in episode 7.
*CORRECTION*
We got our wires crossed with the Intel 4004, which we discuss later. The 74181 was introduced by Texas Instruments in 1970 but appeared in technical manuals around 1969. The design of the 74181, like most of the 74xx/74xxx series, was an open design which was manufactured by many other companies - Fairchild was one such manufacturer. They produced a chip, the Fairchild 9341, which was pin-for-pin compatible with the 74181.
Fairchild was the first to prototype an ALU, building the Fairchild 4711 in 1968 - a one-off device not optimized for scale manufacturing. In 1969, Signetics came out with the 8260, which they marketed in a very limited sense (it was attached, AFAICT, to one particular computer, the Data General SUPERNOVA). TI follows afterwards (March 1970) with the 74181, coupled with the 9341 from Fairchild. The 74181 became the standard number for this part, and was available from many manufacturers (back in those days, chip makers cross-licensed designs all over the place in order to provide assurance that their part could be sourced from multiple manufacturers).
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In which Craig Benzine teaches you about the US Governments Separation of powers and the system of checks and balances. In theory, the Legislative Branch, the Executive Branch, and the Judicial Brach are designed to keep each other in check and to keep any branch from becoming too powerful. In reality, the system was designed to keep the President from becoming some kind of autocrat. For the most part, it has worked. Craig will call in the clones to explain which powers belong to which branches and to reveal some secret perks that the Supreme Court justices enjoy.
Produced in collaboration with PBS Digital Studios: http://youtube.com/pbsdigitalstudios
Support is provided by Voqal: http://www.voqal.org
Chapters:
Introduction 00:00
Separation of Powers 0:25
Checks & Balances 2:28
Legislative Branch powers over the Executive Branch 2:58
Legislative Branch powers over the Judiciary Branch 3:39
Executive Branch powers over the Legislative Branch 4:37
Executive Branch powers over the Judiciary Branch 4:59
Judiciary Branch powers over the Legislative & Executive Branches 5:20
Why do we have checks & balances? 6:22
Credits 7:58
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In which Craig Benzine teaches you about federalism, or the idea that in the United States, power is divided between the national government and the 50 state governments. Craig will teach you about how federalism has evolved over the history of the US, what powers are given to the federal government, and what stuff the states control on their own. And he punches an eagle, which may not surprise you at all.
Produced in collaboration with PBS Digital Studios: http://youtube.com/pbsdigitalstudios
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Chapters:
Introduction: Federalism 00:00
What is Federalism? 0:38
Dual Federalism 1:47
The Commerce Cause 3:34
Cooperative Federalism 4:18
Grants-in-aid 4:48
Regulated Federalism 6:04
New Federalism 7:00
Federalism Today 8:05
Credits 8:44
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THE FINAL SHOWDOWN! This is the last episode on the immune system and also the very last episode of Crash Course Anatomy & Physiology. In it, Hank explains how the cellular immune response uses helper, cytotoxic, and regulatory T cells to attack body cells compromised by pathogens. He also explores how cytokines activate B and T cells, and what happens if your immune system goes rogue and starts causing autoimmune trouble.
Pssst... we made flashcards to help you review the content in this episode! Find them on the free Crash Course App!
Download it here for Apple Devices: https://apple.co/3d4eyZo
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***
Chapters:
Introduction: Cells Fight Cells 00:00
Professional Antigen Presenting Cells 1:46
Helper T Cells 4:00
Cytotoxic T Cells 5:23
Immunodeficiencies 6:08
Autoimmune Disorders 7:27
Review 8:26
***
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You’re probably familiar with the basics of magnets already: They have a north pole and a south pole. Two of the same pole will repel each other, while opposites attract. Only certain materials, especially those that contain iron, can be magnets. And there’s a magnetic field around Earth, which is why you can use a compass to figure out which way is north. In this episode of Crash Course Physics, Shini takes us into the world of magnetism!
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We begin our unit on ethics with a look at metaethics. Hank explains three forms of moral realism – moral absolutism, and cultural relativism, including the difference between descriptive and normative cultural relativism – and moral subjectivism, which is a form of moral antirealism. Finally, we’ll introduce the concept of an ethical theory.
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This week Craig continues our conversation on presidential powers by looking at those NOT found in the Constitution - implied or inherent powers. We’ll talk about how the President uses their power to negotiate executive agreements, recommend legislative initiatives, instate executive orders, impound funds, and claim executive privilege in order to get things done. Implied powers are kind of tough to tack down, as they aren’t really powers until they’re asserted, but once they are, most subsequent Presidents chose not to give them up. So we’ll try to cover those we’ve seen so far and talk a little bit about reactions to these sometimes controversial actions from the other branches of Congress.
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This episode is sponsored by Squarespace: http://www.squarespace.com/crashcourse
Chapters:
Introduction: Informal Powers of the President 00:00
Informal powers of the President 0:50
Inherent power to use troops 1:20
War Powers Resolution 2:23
Executive agreements vs. treaties 2:42
CEO of the U.S. 3:31
Legislative Initiative 4:18
Executive orders 5:20
Impounding funds 6:02
Executive privilege 6:20
The importance of presidential precedent 6:56
Credits 7:21
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Now that we’ve started talking about identity, today Hank tackles the question of personhood. Philosophers have tried to assess what constitutes personhood with a variety of different criteria, including genetic, cognitive, social, sentience, and the gradient theory. As with many of philosophy’s great questions, this has much broader implications than simple conjecture. The way we answer this question informs all sorts of things about the way we move about the world, including our views on some of our greatest social debates.
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In which Jacob Clifford and Adriene Hill teach you about Economic Systems and Macroeconomics. So, economics is basically about choices. We'll look at some of the broadest economic choices when we talk about the difference between planned economies and market economies. We'll get into communism, socialism, command economies, and capitalism. We'll look at how countries choose the kind of system they're going to use (spoiler alert: many end up with mixed economies). We'll also look into how individuals make economic choices.
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TO: Everyone
FROM: Martin
To gild refined gold is just silly.
TO: Dana
FROM: Cameron
Still holding out. We're going to make it!
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Hank introduces us to comparative anatomy, which studies the similarities and differences in animal anatomy to support the theory of evolution and the shared ancestry of living things.
References:
Campbell Biology, 9th ed.
CliffsAP Biology, 3rd ed.
Thomas Henry Huxley: http://www.strangescience.net/huxley.htm
Tissues: http://web.jjay.cuny.edu/~acar....pi/NSC/14-anatomy.ht
Divergence time estimates for the early history of animal phyla...
http://www.ncbi.nlm.nih.gov/pm....c/articles/PMC168965
Table of Contents:
1) Comparative Anatomy 0:00
2) Locomotion 1:19
3) Heterotophy 1:41
4) Convergent Evolution 2:40
5) Biolography 3:40
6) Tissues 6:00
a) Epithelial Tissue 6:11
b) Connective Tissue 6:33
c) Muscle Tissue 7:01
d) Nerve Tissue 7:14
7) Organs 7:32
8) Organ Systems 7:39
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How do lenses work? How do they form images? Well, in order to understand how optics work, we have to understand the physics of light. In this episode of Crash Course Physics, Shini talks to us about optical instruments and how they make magnification possible.
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Atoms are a lot like us - we call their relationships "bonds," and there are many different types. Each kind of atomic relationship requires a different type of energy, but they all do best when they settle into the lowest stress situation possible. The nature of the bond between atoms is related to the distance between them and, like people, it also depends on how positive or negative they are. Unlike human relationships, we can analyze exactly what makes chemical relationships work, and that's what this episode is all about.
If you are paying attention, you will learn that chemical bonds form in order to minimize the energy difference between two atoms or ions; that those chemical bonds may be covalent if atoms share electrons, and that covalent bonds can share those electrons evenly or unevenly; that bonds can also be ionic if the electrons are transferred instead of shared: and how to calculate the energy transferred in an ionic bond using Coulomb's Law.
Pssst... we made flashcards to help you review the content in this episode! Find them on the free Crash Course App!
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Table of Contents
Bonds Minimize Energy 01:38
Covalent Bonds 03:18
Ionic Bonds 05:37
Coulomb's Law 05:51
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In our final episode of Crash Course Philosophy, we consider what it means to live a good life. We’ll look at the myth of Sisyphus, Robert Nozick’s experience machine, Aristotle’s eudaimonistic picture of a good human life, and the existentialists’ view that we each determine the value of our own lives. And we’ll think about how you, too, can live the life of a philosopher.
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Today we continue our unit on identity by asking where the mind resides. Hank explains the mind-body problem and several approaches to the question of where our minds reside, including reductive physicalism, substance dualism, and mysterianism.
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What's that smell? Smell's like Organic Chemistry! This week Hank talks about Aromatics and Cyclic Compounds, naming their substituents, resonance, and common reactions & uses.
Pssst... we made flashcards to help you review the content in this episode! Find them on the free Crash Course App!
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Table of Contents
Cyclic Organic Compounds & Naming Their Constituents 1:06
Aromatic Compounds 3:02
Resonance 3:18
Naming Aromatic Compounds 5:05
Common Reactions & Uses 7:24
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