Notes, summaries, assignments, exams, and problems for University

Technological Progress and Innovation

Technological progress was the very heartbeat of the Industrial Revolution. It was not a single invention that changed everything, but rather a continuous process of innovation. Macro-inventions, such as the steam engine or mechanical spinning machines, opened entirely new possibilities. These groundbreaking innovations were then followed by micro-inventions—smaller, cumulative improvements that refined and expanded their use.

In the textile industry, a series of pivotal inventions revolutionized the production of cotton, making Britain the dominant textile exporter by the 19th century. Key advancements included:

• The flying shuttle (John Kay, 1733)
• The spinning jenny (James Hargreaves, 1764)
• The water frame

The Human Respiratory System

By Marco Rios

Ventilation: Air Movement in the Lungs

Pulmonary Ventilation

The total volume of air breathed in and out per minute.

Alveolar Ventilation

The volume of air exchanged between the atmosphere and the alveoli per minute.

The Lungs: Core Organs of Respiration

A pair of organs consisting of the lower part of the respiratory airways, pulmonary circulation, and connective tissue.

Pleural Sacs and Cavity

Thin, fluid-filled membranes that enclose the lungs. The space between the pair is known as the pleural cavity.

Alveolar Cell Types

Type I Cells

Form the walls of the alveoli, facilitating gas exchange.

Type II Cells

Secrete pulmonary surfactant.

Pulmonary Surfactant

A substance that reduces the surface tension of water inside... Continue reading "Human Respiratory System Functions" »

Ancient Conflicts and Historical Thought

The Peloponnesian War: A Total Conflict

The Peloponnesian War (431–404 BC), fought between Athens and Sparta, was a pivotal conflict in ancient Greek history. Its vast scale, severe destruction, and far-reaching sociopolitical impact make it one of the earliest known examples of what would later be called "total war." The eventual defeat of Athens, brought about in part by Persia's crucial support for Sparta, ushered in a period of Spartan dominance. Historian Arnold Toynbee described Sparta as an "arrested civilization," referring to its inflexible militaristic society and resistance to cultural progress.

Although the term "Total War" was coined by Erich Ludendorff in 1935 in the aftermath of World War... Continue reading "Pivotal Eras: Ancient Conflicts, French Revolution, American Independence" »

Physical Adsorption (Physisorption)

• It occurs due to weak van der Waals forces between the adsorbent and adsorbate.
• The enthalpy of adsorption is low, typically between 20–40 kJ/mol.
• It is usually non-specific and can occur on many types of surfaces.
• It is reversible in nature and can be undone by changing pressure or temperature.
• Physisorption is favored at low temperatures.
• It can result in the formation of multiple layers of adsorbed molecules.
• Little to no activation energy is required for physisorption.

Chemical Adsorption (Chemisorption)

• It involves the formation of strong chemical bonds (covalent or ionic) between the adsorbent and adsorbate.
• The enthalpy of adsorption is high, ranging from 40–400 kJ/mol.
• It is highly specific and depends on

What is a Profession?

Definitions and Traits

What is the difference between a profession and an ordinary job? Here are some key definitions and traits:

• Dictionary Definition: According to Littrich & Murray, citing the Oxford English Dictionary, a profession is “a vocation or calling, especially one that involves some branch of advanced science or learning.”
• Common Traits (Millerson in Littrich & Murray):
  • Skill based on a body of theoretical knowledge.
  • Provision of training and education.
  • Testing competence prior to entrance.
  • Organisation.
  • A code of ethics.
  • An ethos of altruistic service.
  • Selflessness.
• Dal Pont’s Common Attributes of a Profession:
  • Special skill and learning.
  • Public service.
  • Differentiates from other professions.
  • Self-regulation

Key Features of a Business

The key features of a business generally include the following:

1. Economic Activity: Business is primarily an economic activity involving the production and distribution of goods and services to satisfy human needs and earn profits.
2. Profit Motive: One of the main goals of a business is to earn profits. Profit acts as a reward for the risk and effort involved.
3. Risk and Uncertainty: Every business involves some degree of risk and uncertainty due to changing market conditions, competition, customer preferences, and other factors.
4. Production or Procurement of Goods and Services: Businesses either manufacture products or procure goods and services for resale to customers.
5. Sale or Exchange: A business involves the sale or exchange

Common Bus System Explained

The common bus system is an architecture where a single bus is used for communication between various components of a computer, such as memory, registers, and the ALU. This system minimizes the number of pathways required, thereby simplifying the design and saving space.

Components of a Common Bus System:

• Set of Registers (R1, R2, ...)
• Arithmetic Logic Unit (ALU)
• Control Unit
• Common Bus
• Memory Unit

Operation of a Common Bus System:

• Only one register can place its contents on the bus at a time.
• A control unit uses selection lines and control signals to manage data transfers.
• A multiplexer selects which register’s data will go onto the bus.
• A decoder selects the destination register to receive the data.

Advantages:

• Reduces hardware