Physical Science Vocabulary Part 2

Front 1

magnet

Back 1

all domains of a substance are aligned in the same direction (domains...atoms cluster together in microscopic groups)

Front 2

current electricity

Back 2

movement of energy from one place to another; also called electric energy

Front 3

circuit

Back 3

poles of electric energy source must be connected to each other

Front 4

series circuit

Back 4

devices that are connected in a row; single path

Front 5

parallel circuit

Back 5

devices that are on separate paths; do not pass through one device to get to another

Front 6

electromagnet

Back 6

made using coil, iron, and battery; a magnet run by electricity that can be turned on and off

Front 7

chemical energy

Back 7

a form 0f potential energy stored in reactants; usually changes to heat or light energy when it is given off

Front 8

nuclear energy

Back 8

the energy that holds protons and neutrons together in an atom's nucleus

Front 9

fission

Back 9

occurs when a nucleus breaks into two parts

Front 10

fusion

Back 10

occurs when two nuclei join together to form the nucleus of a single larger atom

Front 11

waves

Back 11

disturbances that travel through matter or space, carrying energy from one place to another without carrying matter along with it

Front 12

parts of a wave

Back 12

crest - highest point

trough - lowest point

amplitude - half the wave height

wavelength - measured between any two identical points on a wave

Front 13

frequency

Back 13

the number of crests of a wave that move past a given point in a given unit of time

Front 14

sound

Back 14

produced vibrations of objects; cannot travel through a vacuum (empty space); must have matter to travel through

Front 15

pitch

Back 15

perception of the frequency of a sound as being high or low; A high pitch sound corresponds to a high frequency sound wave and a low pitch sound corresponds to a low frequency sound wave.

Front 16

loudness

Back 16

The loudness of a wave depends on its energy. The greater the energy the louder the sound. The greater the energy the greater the amplitude (height) of the sound wave.

Front 17

electromagnetic spectrum

Back 17

The entire range of electromagnetic radiation. At one end of the spectrum are gamma rays, which have the shortest wavelengths and high frequencies...then come x-rays, ultraviolet, visible light, infrared, microwaves... and at the other end are radio waves, which have the longest wavelengths and low frequencies.

Front 18

reflection

Back 18

bouncing of light waves off of a surface

Front 19

refraction

Back 19

bending of light waves when it passes from one medium to another

Front 20

transparent

Back 20

light can travel through; allows objects to be seen clearly through it

Front 21

translucent

Back 21

material lets light pass through (scatters the light), but objects on the other side can't be seen clearly

Front 22

opaque

Back 22

material that light can't travel through

Front 23

force

Back 23

push or pull

Front 24

speed

Back 24

measure of how far something travels during a period of time; distance/time

Front 25

average speed

Back 25

total distance divided by total time

Front 26

velocity

Back 26

the speed of an object in a particular direction; distance/time + direction

Front 27

momentum

Back 27

mass times velocity

Front 28

law of conservation of momentum

Back 28

momentum before a collision = momentum after collision as long as no other force acts upon it

Front 29

Newton's 1st law of motion

Back 29

an object at rest tends to stay at rest, and an object in motion tends to stay in motion in a straight line until an outside force acts upon it

Front 30

Newton's 2nd law of motion

Back 30

force = mass x acceleration; acceleration is the rate of change in velocity

Front 31

Newton's 3rd law of motion

Back 31

for every action force, there is an equal and opposite reaction force

Front 32

friction

Back 32

two surfaces rub against each other

Front 33

work

Back 33

occurs when a force causes an object to move in the direction of the applied force;

work = force x distance

Front 34

power

Back 34

the amount of work done per unit of time

Front 35

machine

Back 35

any device that makes doing something easier

Front 36

efficiency

Back 36

the ratio between the work done by a machine and the work put into it

Front 37

simple machine

Back 37

a device with few, if any, moving parts that makes it easier to do work

Front 38

lever

Back 38

a simple machine consisting of a bar and a pivot point known as the fulcrum

Front 39

wheel and axle

Back 39

a simple machine that consists of a wheel that applies an effort force and a smaller axle that produces an output force

Front 40

pulley

Back 40

a grooved wheel that turns by the action of a rope in the groove

Front 41

inclined plane

Back 41

a straight, slanted surface that can multiply an effort force

Front 42

screw

Back 42

a simple machine made of an inclined plane wrapped around a central bar that can multiply an effort force

Front 43

wedge

Back 43

an inclined plane that changes the direction of an applied force

Front 44

compound machine

Back 44

when two or more simple machines are combined