a disturbance that transfers energy from one place to another


for transverse waves: the distance between the resting point (or equilibrium) to the crest or trough


the number of waves passing a fixed point in a certain amount of time; it is based partly on wavelength (longer wavelengths take a longer time to pass) and partly on the speed the wave travels


any substance that a wave moves through

mechanical wave

waves that transfer energy through matter


the distance from one wave crest to the very next crest. (This may also be measured from trough to trough.)


the bouncing back of a wave as it strikes a barrier


the bending of a wave as it enters a new medium at an angle other than 90 degrees


the spreading out of waves through an opening or around the edges of an obstacle


the meeting and combining of waves

destructive interference

when waves cancel each other out

constructive interference

when waves combine to a larger amplitude

2 relationships for waves

1) speed and frequency = directly proportional
(as speed goes up, frequency goes up)
2) wavelength and frequency = inversely proportional
(as wavelength gets longer, frequency goes down)

reflection examples

mirror (light waves), echo (sound waves), RADAR (radio waves)

refraction examples

a straw looks "broken" when you look at it in a glass of water (because the light bends when it enters the water)

diffraction examples

light will bend around a lampshade; sounds can be heard even if you are hiding behind something

EM Wave

electromagnetic wave; moves energy through space (sometimes empty space, sometimes through a medium - DOES NOT REQUIRE A MEDIUM)

Examples of EM Waves

Radio, infrared (IR), light

Examples of mechanical waves

Sound, ocean waves, earthquakes


the AVERAGE kinetic energy of an object's particles due to non-directional motion at the atomic level

Heat flow

always goes from hot to cold


the direct transfer of heat from one substance to another substance that it is touching


the transfer of heat by the circulation or movement of a liquid or gas


the transfer of heat by rays or waves

Conduction (examples)

stovetop, seat-warmer

Convection (examples)

oven, blood (circulating), furnace

Radiation (examples)

sun, heat lamp

Melting point of water in °F


Melting point of water in °C


Melting point of water in K


Boiling point of water in °F


Boiling point of water in °C


Boiling point of water in K


Absolute Zero

the temperature at which particles stop moving entirely (impossible to actually reach)


the TOTAL kinetic energy of an object's particles due to non-directional motion at the atomic level

converting Celsius to Kelvin

C + 273 = K

converting Fahrenheit to Kelvin

must convert to Celsius first, THEN to Kelvin

Which temperature scale can be used for calculations in science?


Why do we have the Kelvin scale?

1) Absolute zero is zero
2) There are no negative temperatures

specific heat

The price you pay (in energy) to change the temperature of something.

high specific heat

difficult to change the temperature

example of high specific heat


low specific heat

easy to change the temperature

example of low specific heat


SI unit for speed/velocity

m/s (meters per second)

SI unit for acceleration

m/s² (meters per second squared)

Positive accelerations

speed is increasing

Negative accelerations

speed is decreasing

Acceleration is zero

the object is not chaning speed (is not moving or is moving with constant speed)

Positive velocity

object moving forward

Negative velocity

object moving backwards

Velocity is zero

object is not moving


speed and direction

Graph: distance vs. time (slope)

slope = velocity

On a distance vs. time graph, constant velocity is represented by

A straight line

(distance vs. time) constant speed forward

straight line, positive slope

(distance vs. time) standing still

straight line, slope = 0 (line is flat)

(distance vs. time) speeding up (accelerating)

smiling curve (slope gets steeper and steeper)

(distance vs. time) slowing down

frowning curve (slope gets flatter and flatter)


the force that opposes motion between two surfaces that are touching


when the only force acting on an object is gravity

equal and opposite forces

whenever a force is exerted, there is another force that is equal in size and opposite in direction


objects in motion tend to stay in the same motion; objects at rest tend to stay at rest


mass x speed

zero (momentum)

an object at rest has ______ momentum

SI Unit for force

N (Newton)

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