General Science Lecture Pointers

These flashcards provide vocabulary terms and definitions covering general science concepts, physics, geology, atmospheric layers, and astronomy based on the lecture notes.

Science

A systematic study concerned with facts, principles, and methods that could be observed in our natural, physical, and social environment; derived from the Latin word 'scire', meaning 'to know'.

Physics

The study of matter and energy and the interactions between them, including subjects such as gravity, light, and time.

Louis Pasteur

A chemist who discovered pasteurization, which is the process of heating liquids like milk to kill harmful germs.

Geology

The science of the origin, history, and structure of the Earth, including the physical, chemical, and biological changes it experiences.

Meteorology

The science that deals with the atmosphere and its phenomena, such as weather and climate.

Scientific Method

The logical method used by scientists to acquire knowledge and explain different phenomena in nature.

Hypothesis

An 'educated guess' formulated based on gathered information or data.

Independent Variable

The experimental factors that are intentionally changed during a scientific experiment.

Dependent Variable

The factors that change as a direct result of changes made to the independent variable.

Law

A statement which describes what happens in nature but does not explain the cause of the occurrence.

Theory

A hypothesis that can be explained from observations.

Technology

The application of scientific knowledge to practical purposes, categorized into machines, products, and processes.

SI Basic Quantities

The seven basic quantities in the International System of units: Length (meters), Mass (kilograms), Time (seconds), Electric current (amperes), Temperature (Kelvin), Amount of substance (moles), and Luminous intensity (candelas).

Celsius to Fahrenheit Formula

The formula used to convert Celsius to Fahrenheit: $F = \frac{9}{5}C + 32$.

Kelvin Scale

An absolute temperature scale defined as $1/273.16$ of the triple point of pure water; the conversion formula is $K = °C + 273$.

Density

The mass of an object per unit volume, represented by the formula $D = \frac{\text{Mass}}{\text{Volume}}$; substances denser than water ($1\text{\thinspace g/cc}$) will sink.

Inertia

The tendency of an object to remain at rest or maintain its motion unless disturbed by a force.

Work

In science, this is performed only when the force applied to an object actually moves the object in the direction of the force, represented as $W = F \times d$.

Joule

The unit for work equal to a Newton-meter ($Nm$).

Simple Machines

Mechanical devices having only one or two parts, including the lever, pulley, wheel and axle, inclined plane, wedge, and screw.

Conduction

The method of heat transfer where heat is passed from molecule to molecule through collisions within a material.

Convection

Heat transfer occurring when a gas or liquid moves from one place to another due to temperature differences.

Big Bang Theory

The theory that the universe began $13.7$ billion years ago from a super-massive gaseous point that exploded and sent super-heated particles throughout space.

Earth's Inner Core

A solid, dense ball of iron and nickel which is approximately $780\text{\thinspace miles}$ ($1,250\text{\thinspace km}$) thick.

Earth's Mantle

The layer above the core that is approximately $1,800\text{\thinspace miles}$ thick and makes up nearly $80$ percent of the Earth's total volume.

Subduction

The process occurring when one tectonic plate bends beneath another, often causing the subducted plate to melt in the asthenosphere.

Diastrophism

The process involving movements of the earth's crust such that portions are pushed up, pushed down, or forced sideways, including folding and faulting.

Igneous Rocks

Rocks formed when molten rock (magma) from within Earth cools and solidifies; examples include granite, basalt, and obsidian.

Metamorphic Rocks

Sedimentary or igneous rocks that have been transformed by heat, pressure, or both deep within the Earth.

Troposphere

The lowest layer of the atmosphere measuring about $7\text{\thinspace miles}$ ($12\text{\thinspace km}$), where weather happens and over $75$ percent of atmospheric gases are found.

Ionosphere

A part of the thermosphere made of ionised gas particles that has the quality of bouncing radio signals transmitted from Earth.

Sea Breeze

A cool breeze that blows off the water toward land because land absorbs solar energy and warms neighboring air faster than water does.

CFCs (Chlorofluorocarbons)

Stable substances used in coolants that can release atomic chlorine when exposed to UV radiation; one chlorine atom can destroy over $100,000$ ozone molecules.

Red Shift

The observation that light received from distant stars shifts toward the red area of the spectrum, suggesting stars are traveling away and the universe is expanding.

Milky Way

A spiral-shaped galaxy about $100,000\text{\thinspace light-years}$ in diameter containing roughly $200$ billion stars.

Asteroids

Small bodies orbiting the Sun that resemble planets, most of which are found between Mars and Jupiter.

Comets

Objects made of frozen dust and gases described as 'large, dirty snowballs' that travel on elongated orbits around the Sun.

Black Hole

The final phase of some massive stars created by total gravitational collapse, making it so dense that even light cannot escape.

Jupiter

The largest planet in the solar system, featuring 'the Great Red Spot', which is an intense windstorm larger than Earth.

Triton

The largest moon of Neptune, featuring active nitrogen crystal volcanoes and a surface temperature of $-390°F$, the coldest object in the solar system.