Notes, abstracts, papers, exams and problems of Physics

What is Matter?

Matter is the ‘element’ from which everything is made. It is any substance that has mass and takes up space by having volume.

Where Does Matter Come From?

A billionth of a second after the Big Bang, an important part of the symmetry of the universe was broken. Known as electroweak symmetry breaking, this was the moment when subatomic particles acquired mass for the first time.

What Processes Lead to the Creation of Matter?

A billionth of a second after the Big Bang, electroweak symmetry breaking occurred, and subatomic particles acquired mass for the first time. Among these particles were quarks. As the universe cooled, these quarks combined to form larger, more complex structures: protons and neutrons. Way before the universe... Continue reading "The Origin and Abundance of Matter in the Universe" »

Review

1 Balancing Moments

• seesaw: sube y baja 4
• Perpendicular: At a 90 degree angle to something
• Newton: The unit of measurement of force
• Clockwise: In the same direction as the movement of the hands on a clock
• Counterclockwise: In the opposite direction to the movement of the hands on a clock

Diagram

• a-You have to calculate the moment
• b-The wheel turns more easily when you spin it from near the rim. The distance

M=fd
F=30N
M=fd

Left is 2FI, same result
d=15cm
M=(30) (0.15)=4.5

Right is 2dF, same result
0.15m
M=4.5Nm

2 Making a Scale

• Spring constant: A measure of how stiff or strong a spring is
• Extension: The increase in the length of something
• Elastic: A material able to resume its original shape after being stretched or compressed
• Elastic Limit: The extent to

Thermal Energy and Matter

Work and Heat

Heat is the transfer of thermal energy from one object to another because of a temperature difference. Heat flows spontaneously from hot objects to cold objects. Temperature is a measure of how hot or cold an object is compared to a reference point. On the Kelvin scale, absolute zero is defined as a temperature of 0 kelvins. As an object heats up, its particles move faster, on average. The average kinetic energy of the particles increases. One way that heat flows is by the transfer of energy in collisions. On average, high-energy particles lose energy. Low-energy particles gain energy.

Thermal Energy

Thermal energy is the total potential and kinetic energy of all the particles in an object and depends on... Continue reading "Thermal Energy and Matter: Heat, Temperature, and Specific Heat" »

Newton's Law of Universal Gravitation

What is Gravity?

Sir Isaac Newton described gravity as a force of attraction between all objects. This force is proportional to the masses of the interacting bodies. The more massive the objects, the stronger the gravitational pull between them.

The Moon's Rotation

. How is it that gravity is so weak yet so influential? Although gravity it is considered to be the weakest force of nature, it may be weak here on Earth, but it's not so weak across the cosmos. This invisible force varies on all the planets in the solar system and on the exoplanets we've discovered orbiting other suns. And that's because gravity is an additive force. It scales with mass, so the more massive the planet or star, the stronger its... Continue reading "Unraveling the Mysteries of Gravity: From Newton to Black Holes" »

Who Discovered the Finite Speed of Light?

Ole Romer, a Danish astronomer, discovered that light is not instantaneous. He observed that the emergence of Io from behind Jupiter varied depending on the position of the two planets in the sun's orbit. This led him to realize that light takes time to travel from Jupiter to Earth, causing the observed differences in emergence time.

Understanding the Speed of Light

The speed of light is a fundamental constant, moving through space at a finite speed of 299,792,458 meters per second.

Exploring Light Years and Galaxies

A light year is both a measure of distance and time, representing the distance light travels in one year. Andromeda, a spiral galaxy, is nearly the same size as the Milky Way and is home to... Continue reading "Unveiling the Mysteries of Light and the Universe" »

Eric Blair, better known as George Orwell, was born in 1903 in Bengal, in the then British colony of India. English novelist, essayist, journalist, and critic. Orwell was closely connected to his work, in the sense that both he and his writing were the same – he liked to write from experience, which is not very usual among writers.

As for his family, they were from the middle-class. He wasn't very close to his father. His mother took him to England when he was very young, where he had a happy childhood in the countryside and developed an appreciation for the rural English landscape.

At the age of 8, Eric Blair started studying in one of the most successful boarding schools in England at the time: St Cyprian's School. Young Eric attended St... Continue reading "George Orwell: A Life of Struggle and Triumph" »

Native American Literature

The Notion of the Indian

Indian / Native American - Stereotypes - Homogenizing / great diversity (over 500 tribes) - Othering - A non-presence, a void to be occupied.

The American Indian Movement

«Red Power» Influenced by the black civil rights movement - Pan-Indian identity - Occupation of Alcatraz Island (1969) «Trail of Broken Treaties» - march on Washington, 1972 - Native American Demands the 20-point proposal

Native American Literature

Originally oral cultures: myths and rituals, songs, poems, narrative tales, legends, parables. Oral works translated into English by ethnologists. First novels: John Rollin Ridge’s The Life and Adventures of Joaquín Murieta (1857); Wynema, by Sophia Alice Callahan (1891).

Literary

Voltage: Energy per Electron Provided by the Battery

Energy spent by each electron in a receiver.

Electric Resistance: Opposition of a Material to the Flow of the Electric Current

Electric Current: Number of Electrons that Flow Through the Conductor in 1 Second

Magnitude

• Voltage: V (volts)
• Electric Current: A (amps)
• Resistance: Ω (ohms)
• Power: W (watts)
• Energy: I or KWH (joules)

Alternating Current

• Generated in power plants
• V and I change with time (50 times in 1 second)
• Electrons change their direction of movement
• Consumed by lamps

Direct Current

• Produced by batteries and solar cells
• I and V are constant
• Electrons move always in the same direction
• Consumed by TV, control, alarm clock, calculator, mobile phone, laptop, computer

AC/DC

Effects of Electric Current

• Heat
• Light:

Key Facts

Full Title · Death of a Salesman: Certain Private Conversations in Two Acts and a Requiem

Author · Arthur Miller

Type Of Work · Play

Genre · Tragedy, social commentary, family drama

Language · English (with emphasis on middle-class American lingo)

Time And Place Written · Six weeks in 1948, in a shed in Connecticut

Date Of First Publication · 1949

Original Publisher · The Viking Press

Climax · The scene in Frank’s Chop House and Biff’s final confrontation with Willy at home

Protagonists · Willy Loman, Biff Loman

Antagonists · Biff Loman, Willy Loman, the American Dream

Setting (Time) · “Today,” that is, the present; either the late 1940s or the time period in which the play is being produced, with “daydreams” into Willy’s... Continue reading "Death of a Salesman: Key Facts, Themes, and Motifs" »

What is Force?

Force is a push or pull that can deform an object or change its state of rest or motion.

Types of Forces

• Contact
• Non-contact
• Instantaneous
• Constant

Formula of Force

F = m • a

Difference Between Force and Weight

Weight is a force. Everything on Earth is pulled down towards the ground by gravity. The weight of an object is how hard gravity pulls down on it.

Larger objects get pulled more strongly, so they weigh more than smaller objects. When scientists want to talk about how much stuff is inside something, they talk about mass.

Causes of Force

Forces arise when two or more bodies come into contact. For example, when there is a crash or when you push a door.

Bodies, even if they are not in contact, exert a force on others. For example, the... Continue reading "Understanding Force, Motion, and Newton's Laws" »