Notes, summaries, assignments, exams, and problems for Secondary education

Fundamental Forces in Physics

Weight (W)

• Weight is the gravitational force that exists between masses. Specifically, it is the force exerted on an object by a planet's gravity when the object is at the planet's surface.
• It can be calculated using the formula: W = mg
  • Where: m is the mass of the object under study, measured in kilograms (kg) in the SI unit system.
  • g is the acceleration due to gravity at the planet's surface. On Earth, g ≈ 9.81 m/s².
• Weight is directed along the line connecting the object under study with the planet's center, oriented towards the planet's center.

Normal Force (N)

• The Normal Force is a contact force that acts between two surfaces that are touching each other.
• It is often calculated indirectly, as it balances other forces

Continental Environments

Fluvial (River) Environments

• Stream/river channels
• Sand bars
• Levees
• Floodplains

Lacustrine (Lake) Environments

• Vary in depth, salinity, biological activity, and sediment
• Source sand and mud

Aeolian (Desert) Environments

• Little to no annual precipitation
• Low vegetation
• High wind
• Transport of sand grains
• Dunes contain well-sorted, well-rounded, and frosted (scratched during wind transport) sand grains sand and dust

Paludal (Swamp) Environments

• Area of anoxic (deoxygenated) water where plant material accumulates but cannot decompose (coal)
• Very low energy environment

Glacial Environments

• Glacial meltwater and sediment transport
• Sand, mud, gravel

Transitional Environments

Deltas

• Fan-shaped deposits of sediment
• Coarser sediment is commonly deposited

Latitude: Temperature increases as you go south. Precipitation is higher in the north. Relief: Altitude causes temperature to fall and precipitation to rise. Mountain ranges are barriers that block air masses. The influence of the sea makes coastal temperature milder and increases the contrast in temperature in the interior.

Oceanic Climate: Galicia to País Vasco

Temperature is mild with no great contrasts, cool winters, and mild summers. There is abundant and regular precipitation with very few dry months. Vegetation is characterized by deciduous forests of oaks and beeches, meadows, and grasslands.

Mediterranean Climate: Mediterranean coast and interior

Precipitation is moderate (800-300) and irregular with droughts in summer. Temperature doesn'... Continue reading "Climate and Vegetation Types in Spain" »

Two years ago, I met again with a girl named Maite. Maite and I had been friends since we were little. We met in Barcelona, specifically in the Ramblas of Plaza Cataluña. She used to live here, in La Llagosta, but due to family problems, she had to move to France.

When we met, it was very strange because we didn't know how to react by simply saying hello or hugging each other. When we saw each other, we quickly went towards each other and hugged each other very tightly. It had been two years since we had seen or spoken to each other. We had completely lost touch. We started talking, and I told her that there were times when I talked to her, but she didn't get the messages and she told me that she had changed her cell phone and lost all of her... Continue reading "Reconnecting with Old Friends: Stories of Friendship and Change" »

Epistemology: Philosophical Theories of Truth

In philosophy, epistemic theories of truth are attempts to analyze the notion of truth itself.

The Correspondence Theory of Truth

The Correspondence Theory of Truth states that the truth or falsity of a statement is determined only by how it relates to the world and whether it accurately describes (i.e., corresponds with) that world.

This is a traditional model that goes back at least to some of the classical Greek philosophers.

Positivism and Verification

In the 20th Century, Positivism emerged as a prominent current of the correspondence theory of truth. Positivism defines truth through verification: a proposition is meaningful, and thus capable of being true or false, if and only if it is verifiable... Continue reading "Epistemology: Analyzing Philosophical Theories of Truth" »

8 Essential Information Architecture Principles

The Principle of Objects

This principle focuses on how you see your content. You should try to see it as a living thing—complete with its own lifecycle, behaviors, and characteristics.

The Principle of Choices

People often have the illusion that they want as many choices as possible. However, the more choices we have to make, the more cognitive power it takes for us to actually make the call. This may even cause anxiety. This is why it is better to create specific categories; otherwise, users can easily get lost.

The Principle of Disclosure

People can only process new information in a certain way. This principle is about showing more information depending on the stage or page you are looking for.... Continue reading "8 Essential Information Architecture Principles for UX" »

The Central Dogma of Molecular Biology

Replication - General Characteristics:

• DNA replication is semiconservative: each strand in the DNA double helix acts as a template for the synthesis of a new, complementary strand. The new two daughter molecules of DNA have a new strand and an old one.
• DNA polymerase III: is the enzyme that adds nucleotides to the growing DNA chain, incorporating only those that are complementary to the template. DNA polymerase III has the following characteristics:
  • It can only read a template in 3’-----5’ direction so the new strand grows in 5’----3’ direction.
  • It needs a pre-existing strand of nucleotides called a primer which provides a 3’-OH end to bind new nucleotides.
  • It is able to repair the mistakes by removing

Properties of Metals

PROPERTIES OF METALS: good electrical, thermal and acoustic conductors; ductile and malleable; tough; they melt at high temperatures, expand when the temperature rises and contract when it cools; some are magnetic; rust when they come into contact with air and oxygen (not all); can be recycled and reused, some are toxic for the environment.

Ferrous Metals

FERROUS METALS: main component is iron.

PURE IRON: greyish white colour, good magnetic properties. Disadvantages: only melts at high temperature, difficult to machine, fragile and brittle. Uses: rarely used, used in electronics and electrical components. CAST IRON: very hard and resistant. Uses: machine parts, casing for engines, stands for machines, pistons, street lamps,... Continue reading "Properties of Metals and Ferrous vs. Non-Ferrous Metals" »

DISTILATION PROCESS: ELEMENTS

• Thermometer: measure the temperature of the vapor
• The stopper: hold the thermometer
• The Bunsen Burner: heat the liquid
• The tube at the top of the condenser: conduct the cool water away
• The cool water: cool the vaporized alcohol
• The tube at the bottom of the condenser: conduct cool water in
• The receiving flask: collect the condensed alcohol
• The stand (soporte): maintain an upright or vertical position
• The clamps (pinzas): support the wire
• The wire gauze (rejilla de alambre): spread the flame out
• The ring clamps (pinzas de anilla): grip the flask and the condenser

ORDER

1. Distillation is used...
2. To separate a mixture of liquids...
3. Distillation is a widely used method...
4. The gas is then condensed...
5. Although the term is mostly common.

Receptors

Internal receptors perceive changes inside the body, such as a rise in blood pressure. External receptors perceive stimuli in the external environment.

Types of Receptors

• Mechanoreceptors: Perceive mechanical stimuli (pressure).
• Thermoreceptors: Perceive changes in temperature.
• Chemoreceptors: Detect chemical substances in the air, water, etc.
• Nociceptors: Perceive pain stimuli.
• Photoreceptors: Light sensitive.

Nervous System

The nervous system analyzes internal and external stimuli perceived by receptors, generating responses. It carries out this function through nerve impulses transmitted by cells called neurons. This system coordinates fast, short-lived responses (e.g., muscle contraction).

Endocrine System

The endocrine system is made up... Continue reading "Sensory Systems and Nervous Coordination" »