lecture 1 & 2

What is science?

The application of problem solving to events or features that can be known, using experimentation, description, comparison, and modeling.

What is the Latin root of “science”?

Scientia meaning “knowledge.”

Historically, where did science originate from?

It was an offshoot of philosophy (Greeks, Egyptians), focusing on understanding the physical rather than the metaphysical.

What is knowledge in philosophy?

A justified, true belief.

What two components make up science?

(1) The body of knowledge (concepts, theories, observations), and (2) the process that produces knowledge (testable, accepted methods).

What are the four main scientific methods?

Experimentation, description, comparison, and modeling.

What is experimentation?

Investigating relationships between variables by manipulating one and measuring its effect on another.

What is description in science?

Gathering data through observations and measurements of natural phenomena.

What is comparison in science?

Determining relationships by observing groups exposed to different treatments or circumstances.

What is modeling in science?

Using physical or computer-based models to mimic systems for experiments or observations.

What is analytic truth?

A statement true by definition (e.g., “All bachelors are men”).

What is synthetic truth?

A truth determined by studying the world or conditions of a problem (e.g., “The Earth is not a perfect sphere”).

What is a theory in science?

A mechanism for answering “how” something happens, based on testable, falsifiable predictions.

What makes a good scientific theory?

It must be testable, falsifiable, repeatedly tested, peer-reviewed, and predictive.

What is peer review?

Evaluation by experts in the field before publication to ensure credibility and accuracy.

What is a scientific controversy?

A sustained debate within the scientific community with multiple lines of research, resolved when one side becomes widely accepted.

Who were early atomists in Ancient Greece?

Leucippus and Democritus, who proposed matter is made of indivisible atoms.

What is horror vacui?

Aristotle’s argument that “nothing” cannot exist; therefore, there is no void.

What was Aristotle’s theory of matter?

Matter is composed of four elements (earth, water, air, fire) plus a fifth, aether.

Who rejected Aristotle’s concepts with experiments on inertia and falling bodies?

Galileo Galilei.

What did Galileo discover with telescopes?

Moon’s surface features, Jupiter’s moons, sunspots, and new stars, supporting heliocentrism.

What is the Law of Conservation of Mass?

Mass is neither created nor destroyed in chemical reactions.

Who is the father of modern chemistry?

Antoine Lavoisier, who named hydrogen and proved conservation of mass.

What does the 1st Law of Thermodynamics state?

Energy cannot be created or destroyed, only transformed.

What does the 2nd Law of Thermodynamics state?

In any process, total entropy of a system always increases.

What does the 3rd Law of Thermodynamics state?

The entropy of a perfect crystal at absolute zero is zero.

How old is the universe estimated to be?

About 13.7 billion years.

How old is the Earth?

About 4.54 billion years.

What is visible light?

Electromagnetic radiation in the 380–760 nm range.

Who demonstrated light diffraction, supporting wave theory?

Francesco Grimaldi and Christiaan Huygens.

What did James Clerk Maxwell contribute?

Equations describing electromagnetic waves, forming fundamental laws of electromagnetics.

What did Einstein contribute about light?

Proposed light is made of photons (particles) and explained the photoelectric effect.

What is reflection?

Light bounces off a surface at the same angle it hits it.

What is refraction?

Light bends when passing through mediums of different density.

What is diffraction?

Light bends when passing through a narrow opening, separating wavelengths.

What did Thomas Young’s double slit experiment show?

Light creates interference patterns, proving it behaves as a wave.

What is the Doppler Effect?

The change in frequency of waves when the source moves relative to the observer.

What is red shift in astronomy?

When light shifts to longer wavelengths as objects move away.

Who first measured red shift in stars?

Vesto Slipher.

Who proposed the expanding universe from a single point?

Georges Lemaître.

What did Einstein add to relativity to maintain a static universe?

The cosmological constant.

Who discovered that other galaxies exist beyond the Milky Way?

Edwin Hubble.

What does the Hubble–Lemaître Law state?

A galaxy’s recession speed is proportional to its distance, proving the universe is expanding.