ostalo
We learn a lot about our surroundings thanks to sound. But... what is it exactly? Sound, that is. What is sound? And how does it travel? And what is this doppler effect that we've heard so much about? In this episode of Crash Course Physics, Shini goes over some of the basics (and some of the not-so-basics) of the Physics of Sound.
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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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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.
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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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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Today, we’re going to look at how computers use a stream of 1s and 0s to represent all of our data - from our text messages and photos to music and web pages. We’re going to focus on how these binary values are used to represent numbers and letters and discuss how our need to perform operations on more extensive and more complex matters brought us from our 8-bit video games to beautiful Instagram photos, and from unreadable garbled text in our emails to a universal language encoding scheme.
Produced in collaboration with PBS Digital Studios: http://youtube.com/pbsdigitalstudios
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Why are some countries rich? Why are some countries poor? In the end it comes down to Productivity. This week on Crash Course Econ, Adriene and Jacob investigate just why some economies are more productive than others, and what happens when an economy is mor productive. We'll look at how things like per capita GDP translate to the lifestyle of normal people. And, there's a mystery.
Crash Course is on Patreon! You can support us directly by signing up at http://www.patreon.com/crashcourse
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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!
Download it here for Apple Devices: https://apple.co/3d4eyZo
Download it here for Android Devices: https://bit.ly/2SrDulJ
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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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After serial photography became a thing, it wasn't long before motion pictures started to develop. And, at the front of that development was Thomas Edison, who you may know as an inventor and business person. In this episode of Crash Course Film History, Craig talks to us about Edison, his assistant W.K.L. Dickson, and their inventions that pioneered motion pictures.
Produced in collaboration with PBS Digital Studios: http://youtube.com/pbsdigitalstudios
Want to know more about Craig?
https://www.youtube.com/user/wheezywaiter
The Latest from PBS Digital Studios: https://www.youtube.com/playli....st?list=PL1mtdjDVOoO
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Images Used are in the Public Domain and from the Library of Congress.
***
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Hank describes why plants are so freaking amazing - discussing their evolution, and how their cells are both similar to & different from animal cells.
Watching this after 2023? Here's an updated video about plant cells from Crash Course Botany: https://youtu.be/y9BLCfcUcFg
Table of Contents annotations:
1. Introduction 0:00
2. Plant Evolution 0:56
3. Eukaryotic vs. Prokaryotic Cells 2:33
4. Cellulose and Lignin 3:58
5. Plastids and Chloroplasts 7:05
6. Central Vacuole 8:10
This video uses sounds from Freesound.org
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Today Hank talks about your central nervous system. In this episode, we'll explore how your brain develops and how important location is for each of your brain's many functions.
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: Broca's Aphasia 00:00
Central Nervous System Structure & Function 1:48
Brain Development: Neural Tube 3:27
Brain Development: 3 Primary Vesicles 3:47
Brain Development: 5 Secondary Vesicles 4:04
Brain Development: Major Adult Brain Regions 4:18
Brain Development: Cerebellum & Brain Stem 4:42
Brain Development: Reptilian Brain 5:45
Brain Development: Cerebral Hemispheres 6:35
The Brain's Lobes 7:35
Review 9:14
Credits 9:48
***
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Thank you so much to all of our awesome supporters for their contributions to help make Crash Course possible and freely available for everyone forever:
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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.
Support is provided by Voqal: http://www.voqal.org
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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As we learn more about electricity, we have to talk about fields. Electric fields may seem complicated, but they're really fascinating and a crucial part of physics. In this episode of Crash Course Physics, Shini chats about capacitors, conductors, electric field lines, and how objects with net charge generate electric fields.
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Our exploration of ethical theories continues with another theistic answer to the grounding problem: natural law theory. Thomas Aquinas’s version of this theory says that we all seek out what’s known as the basic goods and argued that instinct and reason come together to point us to the natural law. There are, of course, objections to this theory – in particular, the is-ought problem advanced by David Hume.
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Today we kick off Crash Course Sociology by explaining what exactly sociology is. We’ll introduce the sociological perspective and discuss how sociology differentiates itself from the other social sciences. We’ll also explore what sociology can do, and how a concern with social problems was at the center of sociology's beginnings.
Crash Course is made with Adobe Creative Cloud. Get a free trial here: https://www.adobe.com/creativecloud.html
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Marriage Equality Decision Day Rally photo by Elvert Barnes: https://www.flickr.com/photos/....perspective/18997209
***
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Today, Craig is going to talk about something you fans out there have been demanding for months - money in politics. Specifically, we're going to talk about special interest groups and their role in the U.S. political system. Special interest groups are groups of individuals that make policy-related appeals to government - like the NRA, AARP, or the U.S. Chamber of Commerce. It's all pretty controversial, as money plays an important role in the policies and people these groups influence, so we'll bring in the clones to argue for and against them.
Produced in collaboration with PBS Digital Studios: http://youtube.com/pbsdigitalstudios
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All attributed images are licensed under Creative Commons by Attribution 4.0
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A lot of ionic compounds dissolve in water, dissociating into individual ions. But when two ions find each other and form an insoluble compound, they suddenly fall out of the solution in what's called a precipitation reaction. In this episode of Crash Course Chemistry, we learn about precipitation, precipitates, anions, cations, and how to describe and discuss ionic reactions.
Watch this video in Spanish on our Crash Course en Español channel: https://youtu.be/w_EEk317jnk
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
Download it here for Android Devices: https://bit.ly/2SrDulJ
Table of Contents
Precipitate Reactions 0:34
Determining Precipitates 1:35
Writing Precipitate Reactions 6:31
Calculating Molar Mass Equation 8:52
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So today, Craig is going to try to get inside the heads of voters by discussing how voters make decisions. Now obviously, like all decision making, voter decisions are influenced by a multitude of factors, but the three we are going to focus on today (and the three political scientists seem to think play the biggest role) are party loyalty, the issues involved in an election, and candidate characteristics. Now this all might seem like common sense, and well it sort of is, but it's important to be aware of and take into account the factors that influence our decisions - especially when considering that many voters are not particularly well-informed.
Produced in collaboration with PBS Digital Studios: http://youtube.com/pbsdigitalstudios
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The Physics we're talking about today has saved your life! Whenever you walk across a bridge or lean on a building, Statics are at work. Statics is the study of objects when they're NOT accelerating. In this episode of Crash Course Physics, Shini talks to us about stretching, compressing, and springing as they relate to statics! Also... Game of Thrones.
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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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Hello, world! Welcome to Crash Course Computer Science! So today, we’re going to take a look at computing’s origins, because even though our digital computers are relatively new, the need for computation is not. Since the start of civilization itself, humans have had an increasing need for special devices to help manage laborious tasks, and as the scale of society continued to grow, these computational devices began to play a crucial role in amplifying our mental abilities. From the abacus and astrolabe to the difference engine and tabulating machine, we’ve come a long way to satisfying this increasing need, and in the process completely transformed commerce, government, and daily life.
Produced in collaboration with PBS Digital Studios: http://youtube.com/pbsdigitalstudios
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You're already learning on YouTube — why not get college credit for it? https://link.gostudyhall.com/my1
In this episode of Crash Course: How to College, Erica helps us think about how to best choose the right school for us. There's a lot to think about, like: what kind of learner you are, what kind of environment you like, how to know if your school is looking out for your success, what kinds of support do different schools offer, and of course what do you want to study?
Crash Course: How to College is part of Study Hall, a partnership between ASU and Crash Course. Head over to our new Study Hall channel to check out our Fast Guide series which break down different college majors.
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Follow Study Hall on socials!
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__________________________________________________________________________
Chapters:
0:00 - Introduction
1:00 - How to find the right fit
4:10 - Types of colleges to choose from
5:57 - How to choose
6:21 - Modalities
7:09 - Conclusion
__________________
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Dave Freeman, Hasan Jamal, DL Singfield, Lisa Owen, Jeremy Mysliwiec, Amelia Ryczek, Ken Davidian, Stephen Akuffo, Toni Miles, Erin Switzer, Steve Segreto, Michael M. Varughese, Kyle & Katherine Callahan, Laurel Stevens, Vincent, Michael Wang, Stacey Gillespie (Stacey J), Alexis B, Burt Humburg, Aziz Y, Shanta, DAVID MORTON HUDSON, Perry Joyce, Scott Harrison, Mark & Susan Billian, Junrong Eric Zhu, Rachel Creager, Breanna Bosso, Matt Curls, Tim Kwist, Jonathan Zbikowski, Jennifer Killen, Sarah & Nathan Catchings, team dorsey, Trevin Beattie, Divonne Holmes à Court, Eric Koslow, Jennifer, Dineen, Indika Siriwardena, Khaled El Shalakany, Jason Rostoker, Shawn Arnold, Siobhán, Ken Penttinen, Nathan Taylor, Les Aker, ClareG, Rizwan Kassim, Alex Hackman, Jirat, Katie Dean, Avi Yashchin, NileMatotle, Wai Jack Sin, Ian Dundore, Justin, Mark, Caleb Weeks
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Crash Course is on Patreon! You can support us directly by signing up at http://www.patreon.com/crashcourse
Thanks to the following patrons for their generous monthly contributions that help keep Crash Course free for everyone forever:
Dave Freeman, Hasan Jamal, DL Singfield, Lisa Owen, Jeremy Mysliwiec, Amelia Ryczek, Ken Davidian, Stephen Akuffo, Toni Miles, Erin Switzer, Steve Segreto, Michael M. Varughese, Kyle & Katherine Callahan, Laurel Stevens, Vincent, Michael Wang, Stacey Gillespie (Stacey J), Alexis B, Burt Humburg, Aziz Y, Shanta, DAVID MORTON HUDSON, Perry Joyce, Scott Harrison, Mark & Susan Billian, Junrong Eric Zhu, Rachel Creager, Breanna Bosso, Matt Curls, Tim Kwist, Jonathan Zbikowski, Jennifer Killen, Sarah & Nathan Catchings, team dorsey, Trevin Beattie, Divonne Holmes à Court, Eric Koslow, Jennifer, Dineen, Indika Siriwardena, Khaled El Shalakany, Jason Rostoker, Shawn Arnold, Siobhán, Ken Penttinen, Nathan Taylor, Les Aker, ClareG, Rizwan Kassim, Alex Hackman, Jirat, Katie Dean, Avi Yashchin, NileMatotle, Wai Jack Sin, Ian Dundore, Justin, Mark, Caleb Weeks
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