Difference between revisions of "External Knowledge Training"

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== Physics - Introductory Berkeley course ==
 
== Physics - Introductory Berkeley course ==
: ''All notes by [[User:John|John Eagles]]''
+
: ''Main article: [[Physics - Introductory Berkeley course]]''
=== 1 Introduction ===
 
{{#ev:youtube|-12jGGbkvE4|200|right| }} Today i started watching this introductory course in physics. It's a UC Berkeley course given by Richard Muller. He explains physics without using many equations. In this particular lecture he comments quite a bit on 9/11 related physics and dwells on terrorist shoe bombs. He advises the government in such matters, so his views seem a bit politically colored. But he really knows how to present laws of physics in a very understandable and close-to-life manner. I've learned quite some new things from watching this lecture. <br clear="all" />
 
=== 2 Solar technology, coal reserves ===
 
{{#ev:youtube|3BdYIyvQMVQ|200|right| }} Summary of topics lectured about:
 
# Calories of food
 
# Peripheral vision of the eyes detect especially motion
 
# Solar technology
 
# Tilt of the earth & the seasons
 
# Global warming in relation to the forming of clouds. When the climate heats up, more clouds may form and may counter the greenhouse effect.
 
# Canada is 2nd in the world after Saudi Arabia for its oil reserves, but Canada has it stored in oil sand and it's more expensive
 
# Natural gas & shale gas in comparison to oil
 
# Coal reserves: The USA has most reserves, then comes Russia and then China, Australia and India. These reserves are big in terms of energy compared to the world's oil reserves.
 
# Coal and methane can turned into gasoline, but it's still risky in case the oil prices are lowered.
 
# In politics, there's conflict between the issues of global warming and energy security.
 
# Coal is the cheapest form of energy.
 
# IPCC errors
 
# Sequestering CO2 and making clean use of coal
 
# CCS = Carbon Capture & Storage<br clear="all" />
 
=== 3 Temperature scales ===
 
{{#ev:youtube|xDxRjGUgm3E|200|right| }} Topics in this video:
 
# Size of atoms
 
# Density of atoms
 
# What makes atoms move, what gives them the kinetic energy?
 
# Temperature = how much energy do things have
 
# Thermometers
 
# Scales of Celcius, Fahrenheit
 
# Liquid nitrogen experiments
 
# There are ca 1000 x more molecules in a fluid than in a gas of the same substance per volume
 
# Temperature of absolute zero on the Kelvin scale means there is no energy
 
# In the Kelvin scale the amount of energy is proportional to the temperature
 
# A fire extinguisher has liquid CO2
 
# Your subjective temperature measurement
 
# Hot air rises because it's less dense
 
# Conduction, convection, radiation
 
Lecturer is Bob Jacobsen<br clear="all" />
 
=== 4 Thermodynamics intro ===
 
{{#ev:youtube|4gt6dQBLGFg|200|right| }}
 
# The ideal gas law (relationship between volume & temperature)
 
# Movements of small and bigger molecules and atoms
 
# Energy efficiency of engines
 
# Refrigerators
 
# Air conditioners
 
# Entropy = a measure of disorder<br clear="all" />
 
  
=== 5 Satellites, gravity ===
+
== History - The American Revolution - Yale course ==
{{#ev:youtube|h7o-yp1me9w|200|right| }}
+
: ''This is an open Yale course''<ref>[http://oyc.yale.edu/history/hist-116 The American Revolution] by Joanne Freeman is Professor of History at Yale University.</ref>
This lecture is about:
+
=== Introduction: Freeman's Top Five Tips for Studying the Revolution ===
# Friction
+
<div style="float: right; padding: 20px;">{{#widget:youtube|id=shTBSGoYtK0}} </div>
# Movements of satellites
+
<br>
# Why frisbees and airplane wings lift
+
"Professor Freeman offers an introduction to the course, summarizing the readings and discussing the course's main goals. She also offers five tips for studying the Revolution: <br>
# Satellites move with 5 miles per second. They are falling but because the earth is curved, they fall with the earth curve
+
<br>1) Avoid thinking about the Revolution as a story about facts and dates;
# Rockets escape velocity
+
<br>2) Remember that words we take for granted today, like "democracy," had very different meanings;
# Gravity force between two people near to each other is ca mass of a mosquito
+
<br>3) Think of the "Founders" as real people rather than mythic historic figures;
# What does it mean to be weightless
+
<br>4) Remember that the "Founders" aren't the only people who count in the Revolution;
# How do spy satellites work. They have to be close to the ground. It takes them 1 1/2 hour to orbit the earth one time.
+
<br>5) Remember the importance of historical contingency: that anything could have happened during the Revolution." <br clear="all" />
# Unmanned drones
 
# Weather and tv satellites orbit the equator at 22000 miles high and need 24 hours for one cycle: Geostationary satellites
 
# 24 GPS satellites go around in 12 hours.<br clear="all" />
 
=== 6 Newton's laws, inertia, circular motion ===
 
{{#ev:youtube|Q4fDPs5x0pI|200|right| }}
 
Topics explained in this lecture, illustrated with several experiments:
 
# Newton's laws
 
# Inertia
 
# Circular motion<br clear="all" />
 
=== 7 Radiation, radioactivity ===
 
{{#ev:youtube|dU8wqbX5zBY|200|right| }}
 
* Ionizing radiation knocks electrons off atoms.
 
* We're exposed to some amount of ionizing radiation all the time.
 
* Tritium is used in some watches.
 
* Damaging of DNA is what causes cancer.
 
* Sieverts - Grays - rems.
 
* 2500 rems (25 Sieverts) on average causes 1 fatal cancer. It's a probability.
 
* Radiation illness - requires much less than a dose causing cancer.
 
* About percentages of increase of cancer because of radioactivity.
 
* Alpha rays don't penetrate deeply, are stopped by the skin.
 
* X-rays.<br clear="all" />
 
  
=== 8 Global warming, radioactive rays, radiocarbon dating ===
+
=== Being a British colonist ===
{{#ev:youtube|6dgP_HJ6Rbw|200|right| }}
+
<div style="float: right; padding: 20px;">{{#widget:youtube|id=8_ltTMQ6Gsg}} </div>
* Categories of believers and non-believers in global warming.
+
<br>
* Errors in IPCC reports
+
How did early colonists see Britain and how did the mother country look at the colonists? Gradually the cultures diverged.<br>
* He quotes research stating that organic food is unhealthy?!?
+
"Professor Freeman discusses what it meant to be a British colonist in America in the eighteenth century. She explains how American colonists had deep bonds of tradition and culture with Great Britain. She argues that, as British colonists with a strong sense of their British liberties, settlers in America valued their liberties above all else. She also explains that many Americans had a sense of inferiority when they compared their colonial lifestyles to the sophistication of Europe. Professor Freeman discusses the social order in America during the eighteenth century, and suggests that the lack of an entrenched aristocracy made social rank more fluid in America than in Europe. She ends the lecture by suggesting that the great importance that American colonists placed on British liberties and their link with Britain helped pave the way for the Revolution."<br clear="all" />
* Chemotherapy & radiation therapy against cancer, how does it work?
 
* The energy release of exploding a nucleus is typically 1 million times more than energy released in chemical reactions.
 
* In the early universe almost all atoms probably were explosive or radioactive.
 
* Radiocarbon dating with C14, having a half-life time of 6,000 years. C14 is in the atmosphere because of cosmic radiation affecting C atoms. Living organisms take in a percentage of these C14 atoms. The amount of C14 in the atmosphere is constant.
 
* Potassium-Argon dating: A dating method using rocks.
 
* Beta rays are fast electrons.
 
* Alpha rays consist of small nuclei of 2 protons and 2 neutrons that form He atoms when the rays are stopped.
 
* Gamma rays are penetrating, not ionizing colliding particles. They pass through things. They knock off electrons and are very energetic.
 
* X rays are the same as gamma rays but more energetic. X-ray photos create shadows.<br clear="all" />
 
=== 9 Nuclear reactors, uranium, chain reactions ===
 
{{#ev:youtube|W1LkRO2fiVs|200|right| }}
 
This lecture is about:
 
  
* How to get useful energy from radioactive elements.
+
=== Being a British American ===
* Chain reactions and nuclear fission.
+
<div style="float: right; padding: 20px;">{{#widget:youtube|h9xzYVDWO0o}}</div>
* U235 is more radioactive than U238, but there's much less of U235 on earth (U = uranium).
+
<br>
* Enrichment of uranium is removing what you don't want, for example by using centrifuges.
+
"Professor Freeman discusses the differences between society in the American colonies and society in Britain in the eighteenth century. She uses examples from colonists' writings to show that the American colonies differed from British society in three distinct ways: the distinctive character of the people who migrated to the colonies; the distinctive conditions of life in British America; and the nature of British colonial administration."<br clear="all" />
* Depleted uranium.
 
* Natural and oldest man-made nuclear reactors.
 
* The nature of chain reactions.<br clear="all" />
 
=== 10 Nuclear waste, fusion reactors ===
 
{{#ev:youtube|HwVWcWm89xU|200|right| }}
 
* Where to store nuclear waste?
 
* Safety measures for nuclear plants.
 
* Spent fuel rods and spent fuel storage installations.
 
* Nuclear waste transport.
 
* Waste from uranium mines.
 
* Fusion reactors are still not commercially operated.<br clear="all" />
 
  
=== 11 Graphene, electricity basics ===
+
=== "Ever at Variance and Foolishly Jealous": Intercolonial Relations ===
{{#ev:youtube|TdjvD0clJUw|200|right| }}
+
<div style="float: right; padding: 20px;">{{#widget:youtube|id=-W4kU1YFSck}} </div>
* Four different carbon bonds.
+
<br>
* Graphite and graphene. Graphene is a newly produced one-layer sheet of graphite.
+
The early colonies can be grouped in three categories. In the North there were the New England colonies, in the center the Middle colonies and in the South the Southern colonies. Already these early colonies were very different in character.<br>
* Sparks from static electricity.
+
Freeman tells about the differences between these colonies before they finally united in the Revolution. There's some information about young George Washington who made some blunders as a young officer.<br>
* Voltage, currents, resistance.
+
Info on YouTube says: "Professor Freeman discusses colonial attempts to unite before the 1760s and the ways in which regional distrust and localism complicated matters. American colonists joined together in union three times before the 1760s. Two of these attempts were inspired by the necessity of self-defense; the third attempt was instigated by the British as a means of asserting British control over the colonies."<br clear="all" />
* Fuses and circuit breakers.
 
* Electrocution.
 
* Fibrillation of the heart.
 
* AC and DC currents.<br clear="all" />
 
=== 12 Magnetism ===
 
{{#ev:youtube|VFF9R91bKfk|200|right| }}
 
* What is magnetism?
 
* Rare-earth magnets have transformed society.
 
* Rare-earth minerals.
 
* The earth is a magnet.
 
* Magnetism comes about when there is a moving charge.
 
* Magnetic recording, hard disks, credit cards.
 
* Electric generators = moving wires pass a magnet.
 
* Transformers.
 
* Voltage is energy per electron.
 
* Magnetic levitation.<br clear="all" />
 
  
=== 13 Scientific implications of magnetism - Electrical power ===
+
=== Outraged Colonials: The Stamp Act Crisis ===
{{#ev:youtube|3orwDGQI-zs|200|right| }}
+
{{#widget:youtube|id=sbwOop46Dag}}
* Power = voltage x current.
+
<br>
* A moving magnetic field makes voltage and provided there is a conductor, a current.
+
Info on YouTube says: "Professor Freeman concludes her discussion (from the previous lecture) of the three early instances in which the American colonies joined together to form a union. She then turns to a discussion of the Stamp Act crisis, and how American colonists found a shared bond through their dissatisfaction with the Stamp Act. Faced with massive national debts incurred by the recent war with France, Prime Minister George Grenville instituted several new taxes to generate revenue for Britain and its empire. The colonists saw these taxes as signaling a change in colonial policy, and thought their liberties and rights as British subjects were being abused. These feelings heightened with the Stamp Act of 1765. Finding a shared cause in their protestations against these new British acts, Americans set the foundation for future collaboration between the colonies.
* Alternating currents and direct currents (AC and DC).
+
<br>
* Edison's first promoting of his electric bulbs.
+
00:00 - Chapter 1. Introduction: The Albany Congress of 1754 <br>
* High-voltage wires.
+
09:32 - Chapter 2. British Budget Post-French and Indian War, and the Sugar Act <br>
* Smart grids.<br clear="all" />
+
22:24 - Chapter 3. Colonial Responses to the Early Acts, and the Stamp Act <br>
=== 14 Waves ===
+
30:49 - Chapter 4. Limited Liberties in Virtual Representation and the Stamp Act <br>
{{#ev:youtube|oJr04GrV70o|200|right| }}
+
36:02 - Chapter 5. Patrick Henry on the Stamp Act and Conclusion <br clear="all" />
* Seismographs measure the shaking of the ground.
 
* Atoms are basically a kind of waves, quantum waves.
 
* A particle is a wave.
 
* When you shake the vacuum it becomes a wave.
 
* A wave is moving energy.
 
* The old concept of 'aether' is now renamed 'vacuum.'
 
* Different types of waves.
 
* Earthquakes & tsunamis.
 
  
There's a funny interruption of the lecture because of student demonstrations.
+
=== Resistance or Rebellion? (Or, What the Heck is Happening in Boston?) ===
 +
{{#widget:youtube|id=gGRW5nF2Mqs}}
 +
<br>
 +
''Info on YouTube says:'' "Professor Freeman discusses the mounting tensions between the colonists and the British in the late 1760s and early 1770s. The Virginia Resolves were published and read throughout the colonies in 1765, and generated discussion about colonial rights and liberties. Colonies began working together to resolve their problems, and formed the Stamp Act Congress in 1765. Meanwhile, Boston was becoming more radicalized and mobs began acting out their frustration with British policies. Colonists began to believe that the British were conspiring to oppress their liberties, a belief that seemed to be confirmed when the British stationed troops in Boston. The mounting tension between the Bostonians and British troops culminated in the violence of the Boston Massacre in March 1770.<br>
 +
<br>
 +
00:00 - Chapter 1. The Circulation of the Virginia Resolves <br>
 +
03:47 - Chapter 2. The Stamp Act Congress and Parliamentary Thoughts on the Stamp Act<br>
 +
10:11 - Chapter 3. Mob Protests by the Sons of Liberty<br>
 +
15:41 - Chapter 4. The Repeal of the Stamp Act and the Complications of the Declaratory Act<br>
 +
19:39 - Chapter 5. Reactions to the Townshend Acts and Samuel Adams's Propaganda<br>
 +
31:48 - Chapter 6. Different Viewpoints on the Boston Massacre<br clear="all" />
  
 +
=== The Logic of Resistance ===
 +
{{#widget:youtube|akWmZuLRwQA}}
 +
 +
''Notes copied from YouTube:'' "Professor Freeman lays out the logic of American resistance to British imperial policy during the 1770s. Prime Minister Lord North imposed the Intolerable Acts on Massachusetts to punish the radicals for the Boston Tea Party, and hoped that the act would divide the colonies. Instead, the colonies rallied around Massachusetts because they were worried that the Intolerable Acts set a new threatening precedent in the imperial relationship. In response to this seeming threat, the colonists formed the First Continental Congress in 1774 to determine a joint course of action. The meeting of the First Continental Congress is important for four reasons: it forced the colonists to clarify and define their grievances with Britain; it helped to form ties between the colonies; it served as a training ground for young colonial politicians; and in British eyes, it symbolized a step towards rebellion. The lecture concludes with a look at the importance of historical lessons for the colonists, and how these lessons helped form a "logic of resistance" against the new measures that Parliament was imposing upon the colonies.<br>
 +
<br>
 +
00:00 - Chapter 1. Introduction: The Logic of Resistance<br>
 +
03:23 - Chapter 2. North's Intolerable Acts and Colonial Solidarity<br>
 +
11:28 - Chapter 3. The First Continental Congress<br>
 +
19:14 - Chapter 4. Jefferson's Dinner Party and the Influence of Enlightenment Thought on the Colonists<br>
 +
27:24 - Chapter 5. Jefferson's Reflection on Hamilton's Favorite Hero<br>
 +
35:58 - Chapter 6. The Logic of Colonial Unity from the British Perspective<br>
 +
45:48 - Chapter 7. Edmund Burke's Warning and Conclusion"<br clear="all" />
 +
 +
=== Who Were the Loyalists? ===
 +
{{#widget:youtube|id=W5j8TsHAzsA}}
 +
<br>
 +
A question that came up in me watching this: "What legitimizes a group of people to form a new state?" According to Freeman, about half of the Americans sided with the Revolution and the other half with England (the Loyalists). These Loyalists appear to have been given a hard time by the 'Patriots' who wanted Revolution and liberty.<br><br>
 +
''Info on YouTube reads:'' "The lecture first concludes the discussion of the First Continental Congress, which met in 1774. Ultimately, although its delegates represented a range of opinions, the voices of the political radicals in the Congress were the loudest. In October 1774, the Continental Congress passed both the radical Suffolk Resolves and the Declaration and Resolves, which laid out the colonists' grievances with Parliament. The Congress also sent a petition to the King which warned him that the British Parliament was stripping the American colonists of their rights as English citizens. Given such radical measures, by early 1775, many American colonists were choosing sides in the growing conflict, and many chose to be Loyalists. Professor Freeman concludes her lecture with a discussion of the varied reasons why different Loyalists chose to support the British Crown, and what kinds of people tended to be Loyalists in the American Revolution.<br><br>
 +
 +
00:00 - Chapter 1. Introduction: The Loyalists<br>
 +
01:32 - Chapter 2. Radical Voices in the First Continental Congress: the Grand Council and the Suffolk Resolves<br>
 +
17:23 - Chapter 3. Deliberations over Declaration and Resolves, and the Impact of the Continental Association<br>
 +
27:49 - Chapter 4. Taking Sides: The King's Friends, or the Loyalists<br>
 +
37:53 - Chapter 5. Loyalist Demographics<br>
 +
44:46 - Chapter 6. Conclusion
 
<br clear="all" />
 
<br clear="all" />
  
=== 15 More about waves ===
+
=== Common Sense ===
{{#ev:youtube|nsXW6T0eClg|200|right| }}
+
{{#widget:youtube|Dxdqdax4VbQ}}
* Waves have three characteristics:
+
<br>
** Amplitude (height or size)
+
Paine's pamphlet, ''Common Sense'', was read widely and prepared the American mood for revolution against the British monarchy.<br>
** Energy (intensity or power)
+
''Info with video reads:'' "His lecture focuses on the best-selling pamphlet of the American Revolution: Thomas Paine's ''Common Sense'', discussing Paine's life and the events that led him to write his pamphlet. Published in January of 1776, it condemned monarchy as a bad form of government, and urged the colonies to declare independence and establish their own form of republican government. Its incendiary language and simple format made it popular throughout the colonies, helping to radicalize many Americans and pushing them to seriously consider the idea of declaring independence from Britain.
** Speed (small and big waves travel at the same speed)
+
<br><br>
* Strings of music instruments.
+
00:00 - Chapter 1. Introduction: Voting on Voting<br>
* Piano tuning.
+
01:40 - Chapter 2. On Paine's Burial<br>
* Interference of sound waves.
+
05:52 - Chapter 3. Colonial Mindset during the Second Continental Congress<br>
* Sound waves.
+
12:28 - Chapter 4. Serendipity and Passion: The Early Life of Thomas Paine<br>
* Interference of FM radio waves.
+
21:53 - Chapter 5. Major Arguments and Rhetorical Styles in Common Sense<br>
* Mirages.<br clear="all" />
+
33:45 - Chapter 6. Common Sense's Popularity and Founders' Reactions<br>
=== 16 Mechanical waves ===
+
39:16 - Chapter 7. Social Impact of the Pamphlet and Conclusion "
{{#ev:youtube|JwiGZ9fF-Wg|200|right| }}
+
<br clear="all" />
* Mechanical waves transport energy through a medium by elastic deformations.
 
* Characteristics of mechanical waves:
 
** The medium itself has no position, oscillates around a fixed position.
 
** Energy is required to create a wave. The wave transports the energy.
 
** Waves can transmit information.
 
** Waves travel with a fixed speed for a given medium (wave speed).
 
* A wave pulse is a single propagating disturbance.
 
* Periodic waves repeat regularly.
 
* Frequency = cycles per second (Hertz).
 
* Mechanical waves require a medium (inertia of the medium), and a form of restoring force (pushing the medium back to a starting position).
 
* Superposition of waves: Bouncing waves don't affect each other in terms of the speed with which they travel and the energy they carry.
 
* Standing waves form when two identical waves travel in opposite directions.
 
* Standing waves on guitar strings.
 
* 1st, 2nd, 3rd harmonics on strings.<br clear="all" />
 
  
=== 17 Sound, open and closed pipes ===
+
== References ==
{{#ev:youtube|C57MCktYdCc|200|right| }}
+
<references/>
* Sound is longitudinal or compression waves. They can be through any medium with molecules (gas, liquids, solids), not a vacuum.
 
* Sound is pressure waves, or alternating regions of high and low pressure.
 
* Speed of sound in air is ca. 340 m/s.
 
* Air inside a pipe, shock waves inside a pipe.
 
* The closed end in a pipe always feels the maximum pressure of the wave.
 
* At the open end of a pipe the molecules are free to move. It's a pressure node, the pressure doesn't change.
 
* Wind instruments are resonant pipes, open or closed.
 
* A flute is an open pipe.
 
* A clarinet is a closed pipe.
 
* Open pipes have all harmonics.
 
* Closed pipes have only odd harmonics.
 
* Beats.
 
* Doppler effect.<br clear="all" />
 
=== 18 Electricity ===
 
{{#ev:youtube|rv_tJlzT030|200|right| }}
 
* Electricity is transfer of power or information by electrical forces.
 
* Electrostatic force: A fundamental force of nature (like gravity).
 
* Applications:
 
** transfer of power
 
** storing energy in batteries
 
** run appliances
 
** light, heat
 
** transportation
 
** computers, telecommunication, entertainment
 
* This force comes from electrical charges.
 
* Electrons have about 1/2000th of the mass of neutrons and protons.
 
* Electric charges come in two types: Positive and negative.
 
* Protons and electrons have exactly equal and opposite charges.
 
* There is a fundamental unit of charge.
 
* Electrons move much easier than protons.
 
* Conservation of charge:
 
** The universe has no net charge (is what is believed)
 
** We cannot create a positive or negative net charge
 
* The electrostatic force is both attractive and repulsive.
 
* The gravitational force is only attractive.
 
* Electrostatic force : gravity = 4 x 10 to the 42 : 1, so the electric force is much stronger.
 
* Conductors and insulators
 
* Electrostatic potential energy.<br clear="all" />
 
=== 19 Electrical current & circuits ===
 
{{#ev:youtube|vEo42PO7Sj0|200|right| }}
 
* Voltage = Potential energy / charge.
 
* Batteries = Chemical charge pump. Chemicals store energy which is converted to voltage.
 
* Electrical outlets: The ground of an outlet is literally connected to Earth. It is to keep you and the socket at the same voltage.
 
* Solar cells: Directly convert sunlight into electrostatic charge.
 
* For a voltage to provide power, a charge must flow. This is an electrical current.
 
* Negative charges (electrons) flow from negative to positive. The currents flows in the other direction.
 
* Electrical circuits:
 
** Current is usually confined to flow in wires to appliances.
 
** No current can flow in an open circuit.
 
* Electrical power:
 
** Voltage = Potential energy / charge
 
** Current = Charge transfer / time
 
** Power = Voltage x current
 
* Resistance limits the amount of current flow through a circuit for a given voltage.
 
* Voltage drop
 
* Ohm's law: Voltage drop = current x resistance.
 
* Current = Voltage drop / resistance.
 
* Power lost = current<sup>2</sup> x resistance<br clear="all" />
 
=== 20 Magnetism ===
 
{{#ev:youtube|on6y9CD1Nto|200|right| }}
 
* Is closely tied to electricity.
 
* Simple magnets have some analogies to electrical charges.
 
* A magnetic 'charge' is called a magnetic pole.
 
* Two types of poles: North and South.
 
* These poles always appear in opposite pairs. We call this a dipole.
 
* Magnetic dipoles are similar to electric dipoles.
 
* But there is one major difference: Electric positive and negative charges can exist independently but magnetic monopoles don't exist.
 
* Electromagnets:
 
** Oersted in 1820 discovered that electric currents produce magnetic fields.
 
** On the microscopic level electrons orbit in an atom causing electrical currents.
 
** For most atoms these currents cancel because electrons orbit in different directions.
 
** Iron is an exception. Multiple electrons in iron atoms are orbiting in the same direction.
 
** Each atom is a little atomic magnet.
 
** Magnetism is a product of electrical forces.
 
** Magnetic materials, iron and steel, consist of many microscopic atomic magnets. These usually are not aligned.
 
** Faraday showed that a changing magnetic field produces electrical currents.
 
** And electrical currents produce magnetic fields.<br clear="all" />
 
=== 21 Light ===
 
{{#ev:youtube|XM0doXjKtpg|200|right| }}
 
* How do we see an object? Light from the object must enter our eyes as a source of light, as reflected light or as an optical image using lenses or mirrors.
 
* Light is both a wave and a particle, but light doesn't need a medium to travel.
 
* Light interacting with a surface, for ex. water: Light can get absorbed, bounce off or be reflected, pass through or be refracted.
 
* Two types of reflection:
 
# Specular reflection is off a smooth surface, like mirrors. Light is scattered in one direction.
 
# Diffuse reflection is off a rough surface (most surface). Light is scattered in all directions.
 
* Selective absorption: Some colors are preferentially absorbed, other colors are reflected.
 
* Without atmosphere we would see the sky as black. Air preferentially scatters blue light over red light.
 
* Refraction: Light travels slower in any material. The light will turn when it enters the new medium.
 
* Violet light turns more than red light.
 
* Rainbows.
 
* Total internal reflection - light can stay trapped in a denser medium. Application of this principle in fiber optics.
 
* Lasers are coherent light. All laser light has one color and the light travels all in one direction. It is very intense.
 
<br clear="all" />
 
 
[[Category:Divine School]]
 
[[Category:Divine School]]
 
[[Category:Science]]
 
[[Category:Science]]

Latest revision as of 01:53, 7 December 2013

Most of the content of this page was first published on the FB page with the same name.
This page is moderated by John Eagles.

Physics - Introductory Berkeley course

Main article: Physics - Introductory Berkeley course

History - The American Revolution - Yale course

This is an open Yale course[1]

Introduction: Freeman's Top Five Tips for Studying the Revolution


"Professor Freeman offers an introduction to the course, summarizing the readings and discussing the course's main goals. She also offers five tips for studying the Revolution:

1) Avoid thinking about the Revolution as a story about facts and dates;
2) Remember that words we take for granted today, like "democracy," had very different meanings;
3) Think of the "Founders" as real people rather than mythic historic figures;
4) Remember that the "Founders" aren't the only people who count in the Revolution;
5) Remember the importance of historical contingency: that anything could have happened during the Revolution."

Being a British colonist


How did early colonists see Britain and how did the mother country look at the colonists? Gradually the cultures diverged.
"Professor Freeman discusses what it meant to be a British colonist in America in the eighteenth century. She explains how American colonists had deep bonds of tradition and culture with Great Britain. She argues that, as British colonists with a strong sense of their British liberties, settlers in America valued their liberties above all else. She also explains that many Americans had a sense of inferiority when they compared their colonial lifestyles to the sophistication of Europe. Professor Freeman discusses the social order in America during the eighteenth century, and suggests that the lack of an entrenched aristocracy made social rank more fluid in America than in Europe. She ends the lecture by suggesting that the great importance that American colonists placed on British liberties and their link with Britain helped pave the way for the Revolution."

Being a British American


"Professor Freeman discusses the differences between society in the American colonies and society in Britain in the eighteenth century. She uses examples from colonists' writings to show that the American colonies differed from British society in three distinct ways: the distinctive character of the people who migrated to the colonies; the distinctive conditions of life in British America; and the nature of British colonial administration."

"Ever at Variance and Foolishly Jealous": Intercolonial Relations


The early colonies can be grouped in three categories. In the North there were the New England colonies, in the center the Middle colonies and in the South the Southern colonies. Already these early colonies were very different in character.
Freeman tells about the differences between these colonies before they finally united in the Revolution. There's some information about young George Washington who made some blunders as a young officer.
Info on YouTube says: "Professor Freeman discusses colonial attempts to unite before the 1760s and the ways in which regional distrust and localism complicated matters. American colonists joined together in union three times before the 1760s. Two of these attempts were inspired by the necessity of self-defense; the third attempt was instigated by the British as a means of asserting British control over the colonies."

Outraged Colonials: The Stamp Act Crisis


Info on YouTube says: "Professor Freeman concludes her discussion (from the previous lecture) of the three early instances in which the American colonies joined together to form a union. She then turns to a discussion of the Stamp Act crisis, and how American colonists found a shared bond through their dissatisfaction with the Stamp Act. Faced with massive national debts incurred by the recent war with France, Prime Minister George Grenville instituted several new taxes to generate revenue for Britain and its empire. The colonists saw these taxes as signaling a change in colonial policy, and thought their liberties and rights as British subjects were being abused. These feelings heightened with the Stamp Act of 1765. Finding a shared cause in their protestations against these new British acts, Americans set the foundation for future collaboration between the colonies.
00:00 - Chapter 1. Introduction: The Albany Congress of 1754
09:32 - Chapter 2. British Budget Post-French and Indian War, and the Sugar Act
22:24 - Chapter 3. Colonial Responses to the Early Acts, and the Stamp Act
30:49 - Chapter 4. Limited Liberties in Virtual Representation and the Stamp Act
36:02 - Chapter 5. Patrick Henry on the Stamp Act and Conclusion

Resistance or Rebellion? (Or, What the Heck is Happening in Boston?)


Info on YouTube says: "Professor Freeman discusses the mounting tensions between the colonists and the British in the late 1760s and early 1770s. The Virginia Resolves were published and read throughout the colonies in 1765, and generated discussion about colonial rights and liberties. Colonies began working together to resolve their problems, and formed the Stamp Act Congress in 1765. Meanwhile, Boston was becoming more radicalized and mobs began acting out their frustration with British policies. Colonists began to believe that the British were conspiring to oppress their liberties, a belief that seemed to be confirmed when the British stationed troops in Boston. The mounting tension between the Bostonians and British troops culminated in the violence of the Boston Massacre in March 1770.

00:00 - Chapter 1. The Circulation of the Virginia Resolves
03:47 - Chapter 2. The Stamp Act Congress and Parliamentary Thoughts on the Stamp Act
10:11 - Chapter 3. Mob Protests by the Sons of Liberty
15:41 - Chapter 4. The Repeal of the Stamp Act and the Complications of the Declaratory Act
19:39 - Chapter 5. Reactions to the Townshend Acts and Samuel Adams's Propaganda
31:48 - Chapter 6. Different Viewpoints on the Boston Massacre

The Logic of Resistance

Notes copied from YouTube: "Professor Freeman lays out the logic of American resistance to British imperial policy during the 1770s. Prime Minister Lord North imposed the Intolerable Acts on Massachusetts to punish the radicals for the Boston Tea Party, and hoped that the act would divide the colonies. Instead, the colonies rallied around Massachusetts because they were worried that the Intolerable Acts set a new threatening precedent in the imperial relationship. In response to this seeming threat, the colonists formed the First Continental Congress in 1774 to determine a joint course of action. The meeting of the First Continental Congress is important for four reasons: it forced the colonists to clarify and define their grievances with Britain; it helped to form ties between the colonies; it served as a training ground for young colonial politicians; and in British eyes, it symbolized a step towards rebellion. The lecture concludes with a look at the importance of historical lessons for the colonists, and how these lessons helped form a "logic of resistance" against the new measures that Parliament was imposing upon the colonies.

00:00 - Chapter 1. Introduction: The Logic of Resistance
03:23 - Chapter 2. North's Intolerable Acts and Colonial Solidarity
11:28 - Chapter 3. The First Continental Congress
19:14 - Chapter 4. Jefferson's Dinner Party and the Influence of Enlightenment Thought on the Colonists
27:24 - Chapter 5. Jefferson's Reflection on Hamilton's Favorite Hero
35:58 - Chapter 6. The Logic of Colonial Unity from the British Perspective
45:48 - Chapter 7. Edmund Burke's Warning and Conclusion"

Who Were the Loyalists?


A question that came up in me watching this: "What legitimizes a group of people to form a new state?" According to Freeman, about half of the Americans sided with the Revolution and the other half with England (the Loyalists). These Loyalists appear to have been given a hard time by the 'Patriots' who wanted Revolution and liberty.

Info on YouTube reads: "The lecture first concludes the discussion of the First Continental Congress, which met in 1774. Ultimately, although its delegates represented a range of opinions, the voices of the political radicals in the Congress were the loudest. In October 1774, the Continental Congress passed both the radical Suffolk Resolves and the Declaration and Resolves, which laid out the colonists' grievances with Parliament. The Congress also sent a petition to the King which warned him that the British Parliament was stripping the American colonists of their rights as English citizens. Given such radical measures, by early 1775, many American colonists were choosing sides in the growing conflict, and many chose to be Loyalists. Professor Freeman concludes her lecture with a discussion of the varied reasons why different Loyalists chose to support the British Crown, and what kinds of people tended to be Loyalists in the American Revolution.

00:00 - Chapter 1. Introduction: The Loyalists
01:32 - Chapter 2. Radical Voices in the First Continental Congress: the Grand Council and the Suffolk Resolves
17:23 - Chapter 3. Deliberations over Declaration and Resolves, and the Impact of the Continental Association
27:49 - Chapter 4. Taking Sides: The King's Friends, or the Loyalists
37:53 - Chapter 5. Loyalist Demographics
44:46 - Chapter 6. Conclusion

Common Sense


Paine's pamphlet, Common Sense, was read widely and prepared the American mood for revolution against the British monarchy.
Info with video reads: "His lecture focuses on the best-selling pamphlet of the American Revolution: Thomas Paine's Common Sense, discussing Paine's life and the events that led him to write his pamphlet. Published in January of 1776, it condemned monarchy as a bad form of government, and urged the colonies to declare independence and establish their own form of republican government. Its incendiary language and simple format made it popular throughout the colonies, helping to radicalize many Americans and pushing them to seriously consider the idea of declaring independence from Britain.

00:00 - Chapter 1. Introduction: Voting on Voting
01:40 - Chapter 2. On Paine's Burial
05:52 - Chapter 3. Colonial Mindset during the Second Continental Congress
12:28 - Chapter 4. Serendipity and Passion: The Early Life of Thomas Paine
21:53 - Chapter 5. Major Arguments and Rhetorical Styles in Common Sense
33:45 - Chapter 6. Common Sense's Popularity and Founders' Reactions
39:16 - Chapter 7. Social Impact of the Pamphlet and Conclusion "

References

  1. The American Revolution by Joanne Freeman is Professor of History at Yale University.