[General Science] Condensed Notes
Basic Concepts of Science
Botany: Study of plants.
Zoology: Study of animals and animal life.
Genetics: Study of heredity.
Medicine: Science of diagnosing, treating, and preventing illness, disease, and injury.
Science and Technology
Science: Systematic study concerned with facts, principles, and methods observably found in natural, physical, and social environments.
Originates from the Latin "scire," meaning "to know."
Comprises both knowledge and processes, including ways of thinking and solving problems.
Scientific Method
Logical method utilized by scientists for knowledge acquisition, explaining natural phenomena.
Observation: Phenomenon is observed through senses.
Steps in the Scientific Method:
Identify and clearly state the problem (specific, measurable, and attainable).
Gather pertinent information (recall experiences, interview knowledgeable individuals, research).
Formulate a hypothesis (educated guess based on gathered information).
Test the hypothesis (conduct controlled experiments).
Controlled Experiment: Manipulating one factor to observe effects.
Trials: Repeatable experiments to ensure reliability.
Controls: Constant factors in experiments.
Variables: Factors that change during experiments (Independent and Dependent).
Draw a conclusion based on experimental results.
Apply principles to broader situations.
Branches of Science
Physical Sciences: Study matter and energy interactions.
Physics: Study of matter, energy, and their interactions.
Chemistry: Composition and properties of matter.
Astronomy: Study of the universe beyond Earth's atmosphere.
Earth Sciences: Study of Earth's origin, history, and structure.
Geology: Origin and changes of Earth.
Oceanography: Study of oceans.
Meteorology: Study of atmosphere and weather.
Life Sciences (Biology): Study of living organisms.
Technology
Defined as the application of scientific knowledge for practical purposes.
Types of Technology:
Machines: Tools/devices that enhance efficiency (e.g., airplanes, CT scans).
Products: Materials created by artificial or natural processes (e.g., steel).
Processes: Methods of doing things (e.g., food preservation).
Scientific Traits
Curiosity: Keen observation of surroundings.
Logic and System: Systematic approach to experiments.
Open-Mindedness: Willingness to revise ideas as necessary.
Intellectual Honesty: Acknowledging contributions of others.
Hard Work: Persistence in scientific endeavors.
Creativity and Critical Thinking: Using established facts for new theories.
International System of Units (SI)
Measurement is comparing a quantity to a chosen standard.
Basic Units:
Length: Meters (m)
Mass: Kilograms (kg)
Time: Seconds (s)
Electric Current: Amperes (A)
Temperature: Kelvin (K)
Amount of Substance: Moles
Luminous Intensity: Candelas (cd)
Metric Prefixes
Useful for conversions and based on powers of 10.
Common Prefixes:
kilo (10^3), mega (10^6), giga (10^9),
deci (10^-1), centi (10^-2), milli (10^-3),
micro (10^-6), nano (10^-9)
Measurements of Volume
Regular solids: Volume = Length × Width × Thickness (measured in cubic units).
Liquid Volume: Measured in cubic meters and liters (L).
Read measurement of clear liquids from the lower meniscus, colored liquids from the upper meniscus.
Irregular solids: Volume determined by the displacement method (e.g., Archimedes' principle).
Temperature Scales
Fahrenheit: Used mainly in the USA; 32°F freezing, 212°F boiling point of water.
Celsius: Widely used globally; 0°C freezing, 100°C boiling point of water.
Kelvin: SI unit of temperature; 0 K is absolute zero. K = °C + 273.
Force
Defined as a push or pull that changes an object's speed or direction.
Types of Forces:
Gravitational Force: Force of attraction between two masses.
Friction: Resistance to motion between two surfaces.
Centripetal Force: Keeps an object moving in a circular path.
Electromagnetic Force: Responsible for electronic structures in atoms.
Mass vs. Weight
Mass: Quantity of matter (constant) measured in kilograms (kg).
Weight: Gravitational pull on an object, varying with location and distance from Earth.
Work and Energy
Work: Done when a force moves an object (W = Force × Displacement).
Energy: Capacity to do work;
Forms of Energy: Mechanical, Thermal, Electrical, Chemical, Radiant, Nuclear.
Law of Conservation of Energy: Energy cannot be created or destroyed, only transformed.
Heat Transfer Methods
Conduction: Heat transfer through direct contact.
Convection: Heat transfer by the movement of fluids.
Radiation: Transfer of energy through electromagnetic waves.
Earth's Structure and Formation
Core: Inner part composed of iron and nickel.
Mantle: Layer above the core, approximately 1,800 miles thick.
Crust: Earth’s outer shell, composed of oceanic and continental crusts.
Plate Tectonics and Continental Drift
Earth's crust consists of moving tectonic plates causing geological changes.
Types of Rocks and the Rock Cycle
Igneous: Formed from cooled magma.
Sedimentary: Result of sediment compaction.
Metamorphic: Transformed by heat and pressure.
Atmospheric Layers
Troposphere: Where weather occurs.
Stratosphere: Contains the ozone layer that protects from UV rays.
Mesosphere, Thermosphere, Exosphere: Other layers with specific characteristics.
Air Pollution and its Effects
Main pollutants include nitrogen dioxide, sulfur dioxide, carbon monoxide, and lead, each causing various health problems and environmental issues.
Weather vs. Climate
Weather: Short-term atmospheric conditions.
Climate: Long-term average of weather patterns.
Astronomy Basics
Universe estimated to be 13.7 billion years old, containing 4% ordinary matter, 23% dark matter, and 73% dark energy.
The Solar System: Includes the Sun and its orbiting planets, asteroids, and comets.
Life Cycle of Stars: Stars undergo several phases from birth (nebula) to death (black holes, supernova).
Planet Descriptions
Overview of each planet in the Solar System, highlighting unique features and characteristics, including Earth, Mars, Jupiter, Saturn, Uranus, Neptune, and Pluto.