science

Science

Study of the natural world through observation and experiment.

Scientific Method

Step-by-step process in solving scientific problems.

Observation

Gathering information using the senses.

Experiment

Scientific test to discover something.

Hypothesis

Educated guess that can be tested.

Theory

Well-tested explanation of facts.

Law (Science)

Statement describing natural events.

Variable

Factor that can change in an experiment.

Control Group

Group not exposed to the variable.

Data

Collected facts and information.

Conclusion

Final result of an experiment.

Matter

Anything that has mass and occupies space.

Mass

Amount of matter in an object.

Volume

Space occupied by matter.

Density

Mass per unit volume.

Atom

Smallest unit of matter.

Molecule

Two or more atoms combined.

Element

Pure substance made of one type of atom.

Compound

Substance formed by combined elements.

Mixture

Combination of substances not chemically joined.

Solid

State of matter with definite shape and volume.

Liquid

State of matter with definite volume but no fixed shape.

Gas

State of matter without definite shape or volume.

Evaporation

Liquid changing into gas.

Condensation

Gas changing into liquid.

Melting

Solid changing into liquid.

Freezing

Liquid changing into solid.

Sublimation

Solid changing directly into gas.

Energy

Ability to do work.

Kinetic Energy

Energy of motion.

Potential Energy

Stored energy.

Force

Push or pull on an object.

Motion

Change in position of an object.

Gravity

Force pulling objects toward Earth.

Friction

Force resisting motion.

Speed

Distance traveled over time.

Velocity

Speed with direction.

Acceleration

Rate of change in velocity.

Newton’s First Law

Object stays at rest or in motion unless acted upon.

Newton’s Second Law

Force equals mass times acceleration.

Newton’s Third Law

Every action has an equal opposite reaction.

Work

Force applied over distance.

Power

Rate of doing work.

Simple Machine

Tool making work easier.

Lever

Bar that moves around a pivot.

Pulley

Wheel with rope used to lift objects.

Wheel and Axle

Machine reducing effort.

Inclined Plane

Slanted surface used to move objects.

Electricity

Flow of electric charges.

Current

Flow of electricity.

Voltage

Electrical pressure.

Circuit

Path through which electricity flows.

Magnet

Object attracting iron and metals.

Magnetism

Force produced by magnets.

Light

Form of energy visible to the eye.

Reflection

Bouncing back of light.

Refraction

Bending of light.

Sound

Energy produced by vibrations.

Vibration

Back-and-forth movement.

Wave

Transfer of energy through matter or space.

Frequency

Number of waves passing per second.

Earth

Third planet from the Sun.

Solar System

Sun and objects orbiting it.

Planet

Large object orbiting a star.

Star

Huge ball of hot gases producing light.

Galaxy

Group of stars and planets.

Moon

Natural satellite of Earth.

Rotation

Spinning of Earth on its axis.

Revolution

Movement of Earth around the Sun.

Eclipse

Blocking of sunlight by a celestial body.

Tide

Rise and fall of ocean water.

Weather

Daily condition of the atmosphere.

Climate

Long-term weather pattern.

Atmosphere

Layer of gases around Earth.

Water Cycle

Continuous movement of water on Earth.

Precipitation

Rain, snow, or hail falling from clouds.

Earthquake

Sudden shaking of Earth.

Volcano

Opening where magma erupts.

Magma

Molten rock beneath Earth.

Lava

Molten rock on Earth’s surface.

Erosion

Wearing away of land.

Photosynthesis

Plants making food using sunlight.

Chlorophyll

Green pigment helping photosynthesis.

Cell

Basic unit of life.

Tissue

Group of similar cells.

Organ

Body part with specific function.

Organ System

Group of organs working together.

Organism

Living thing.

Biology

Study of living things.

Zoology

Study of animals.

Botany

Study of plants.

Ecology

Study of interactions in the environment.

Habitat

Natural home of an organism.

Ecosystem

Community of living and nonliving things.

Food Chain

Sequence of organisms eating one another.

Producer

Organism making its own food.