Physical Science and Engineering

Spontaneous Reaction

A chemical reaction that occurs when elements are combined even when no extra energy is present.

Neutral (Charge)

a material without a net positive or negative charge

Example.

neutrons

Newton's Third Law

the law that for every action there is an equal and opposite reaction

Example.

If you release the bottom of a balloon, the air rushes out. This movement causes an equal and opposite reaction and the balloon moves up.

Natural Gas

a fossil fuel byproduct formed with coal and oil

Electron Affinity

the ability to accept an electron and become a more negative ion

Example.

Fluorine (group 17) has a higher electron affinity than Oxygen (group 16)

Generator

A device that uses electromagnetic induction to produce an electrical current (mechanical energy to electrical energy).

Example.

Generator within a windmill

Transverse Wave

a wave in which the direction of the vibration is perpendicular to the direction the energy travels

Example.

light, vibrating guitar string

Gravity

a force that pulls all masses towards each other, with or without touching; Earth's gravity pulls all objects near its surface downward

Acceleration

a measure of how quickly something changes its speed or direction, calculated from change in velocity/time

Example.

slowing down, turning a corner

Greenhouse Gases

gases which, when present in elevated quantities in Earth's atmosphere, trap solar radiation and cause the planet to warm

Example.

carbon dioxide

Gravitational Force

the force of attraction of all masses toward each other due to gravitational pull

Example.

Earth pulls on Moon

Solar Energy

energy from the sun in the form of electromagnetic radiation

Weak Nuclear Force

a force that resists particle decay in the nucleus

Example.

radioactive decay

Magnetic Poles

the north and south ends of a magnet

Inertia

the tendency to resist changes in state of motion

Example.

objects at rest stay at rest and objects in motion stay in motion

Electronegativity

the tendency of an atom to attract electrons toward itself

Example.

Fluorine, Oxygen, Nitrogen, and Chlorine are the most electronegative elements, while Francium is the least.

Wave Speed

a measure of how fast the wave energy moves from one place to another

Example.

speed of light

Chemical Reactivity

a measure of the tendency of an atom, molecule, or compound to undergo a chemical change

Solid

a state of matter with particles fixed in place and packed closely together; has a definite shape and volume

Example.

ice

Metallic Character

Elements that show stronger metallic properties such as conductivity, malleability, ductility, and luster; greater in elements that easily lose their valence electrons.

Wave

a disturbance that transports energy as it moves through space and time

Example.

water wave, electromagnetism, sound

Medium

the material that carries a mechanical wave

Example.

air for sound wave, a string for a violin

Metallic Qualities

Qualities typically associated with metals such as magnetism, conductivity, malleability, and ductility

Electromagnetic Waves

Waves consisting of vibrating electric and magnetic fields. Electromagnetic waves can travel through a vacuum because they do not require a medium. Emitted by all objects with a temperature above absolute zero.

Example.

light, radio waves, x-rays

Newton's First Law / The Law of Inertia

the law that objects resist changes in their state of motion

Example.

a rolling bowling ball keeps moving at constant speed

Period

the time it takes to complete one full wave cycle, measured in seconds

Example.

a 17 second stop-light cycle

Combustion Motor

a device that transforms chemical energy into mechanical energy

Example.

car engine

Troughs (of a Wave)

the valleys, or lowest points, of a vertically vibrating transverse wave

Liquid

a state of matter with particles close together but not fixed in place; has a definite volume, but takes the shape of the container

Example.

water

Coal

a fossil fuel formed from land plants

Force

an interaction (push or pull) of one object with another that resists other forces or causes acceleration

Example.

There are only four kinds of forces, called universal (or fundamental) forces: gravitational, electromagnetic, strong nuclear, and weak nuclear

Acid Rain

rain with a lower pH than neutral, corrosive to many substances including rocks, often caused by pollution

Example.

sulfur dioxide dissolves in the water droplets of clouds to make sulfuric acid

Ionization Energy

the amount of energy needed to remove an outer electron to make a positive ion

Example.

Alkali metals have low ionization energies, making them highly reactive.

Mechanical Waves

Physical waves that travel through a medium.

Example.

sound, water waves

Conservation of Energy

in a closed system, the total amount of energy is constant, even if it changes form or moves from one place to another

Example.

girl diving off board into water

Longitudinal Wave

a wave in which the direction of the vibration is parallel to the direction the energy travels

Example.

sound

Charge

an electric property of matter that produces interactions with an electric field; can be positive or negative

Example.

protons, electrons

Amplitude

the maximum displacement of a particle of the medium during a vibration (measured from non-vibrating position to one crest)

Example.

height of an ocean wave above the ocean's normal surface height

Conservation of Matter

Matter cannot be created or destroyed; it only changes form

Example.

chemical reaction

Magnetic Field

the potential magnetic force in the space surrounding a magnet; proportional to the force on a magnetic pole in the space around the magnet

Fossil Fuels

a natural non-renewable fuel source. derived from underground, fossilized (petrified) remains of living organisms.

Example.

natural gas, petroleum, coal

Frequency

the number of ocurrences of an observed behavior over a set time period

Example.

A teacher counting the number of times Jacob sticks his tongue out at a classmate during a one-hour class would be collecting frequency data.

Strong Nuclear Force

a force that holds protons and neutrons together in the nucleus

Example.

fission and fusion

Photovoltaics

panels collect sunlight and turn the energy into electricity

Oil

a fossil fuel formed from marine organisms

Renewable Resources

resources which replenish at the same (or faster) rate than the rate at which they are used

Example.

wind energy, solar energy, hydroelectric power

Electromagnetic Force

interactions (pushes and pulls) of electrically charged particles with other charged particles and magnetic poles

Example.

like charges repel, opposite charges attract

Net Force

The vector sum of all forces acting on an object.

Mass

The amount of matter in an object, measured in kg in the SI system of units.

Turbine

a device that transforms kinetic energy into mechanical energy

Example.

Blades of a windmill

Atomic Radius

the distance from the nucleus to the outer electron shell

Gas

a state of matter with quickly-moving particles that are farther apart than in a liquid; has no definite volume and takes the shape of the container

Example.

water vapor

Ion

an atom with a net electrical charge because it lost or gained an electron

Example.

H+ ion has a +1 charge

Non-Renewable Resources

resources which will be depleted faster than they can be replenished

Example.

natural gas, petroleum

Hydroelectric Energy

energy collected as gravity pulls water from higher elevations to lower elevations

Example.

Hoover Dam

Crests

the peaks, or highest points, of a vertically vibrating transverse wave

Newton's Second Law

the law that greater masses require a greater force to achieve the same acceleration, F = ma

Example.

force needed to stop a bowling ball vs baseball rolling at same speed

Wavelength

the length (in space) of one complete wave cycle, measured in distance units

Example.

crest to crest distance on a water wave