8th physical science exam Flashcards

16303928547	Force	a push or pull applied to an object	0
16303928549	Science	Process that uses observation and investigation to gain knowledge about events in nature	1
16303928550	Net Force	when two or more forces act on an object at the same time	2
16303928551	Scientific Method	an organized set of investigation procedures used by scientists	3
16303928552	Control	standard for comparison	4
16303928554	Hypothesis	A testable prediction	5
16303928556	Static Friction	friction in which two surfaces are not moving past each other	6
16303928557	experiment	organized procedure for testing a hypothesis	7
16303928559	sliding friction	friction where two surfaces slide past one another	8
16303928560	control	standard for comparison	9
16303928561	constant	factor that doesn't vary in experiment	10
16303928562	independant variable	factor that is adjusted by the experimenter	11
16303928563	rolling friction	friction between a rolling object and the surface it rolls on	12
16303928564	independent variable	variable that we change	13
16303928565	fluid friction	The friction when an object moves through a fluid meaning fluid or gas	14
16303928566	dependent variable	dependent on the independent variable	15
16303928567	air resistant	a friction-like force that opposes motion of object that move through air depend on speed, size and shape	16
16303928568	scientific law	pule of nature that sums up related observations to describe a pattern in nature	17
16303928569	velocity	includes the speed of an object and the direction of its motion	18
16303928570	scientific theory	explanation based on experiments, the most logical explanations	19
16303928571	acceleration	rate of change of velocity	20
16303928572	graph	a visual display of information or data	21
16303928573	line graph	shows trends or how the data changes over time	22
16303928574	bar graph	useful for comparing information collected by counting	23
16303928575	Motion	occurs when an object changes position relative to a reference point	24
16303928576	distance	how far an object has traveled	25
16303928577	Displacement	distance an direction of an object's change in position relative to the starting point	26
16303928578	speed	The distance an object travels per unit of time	27
16303928579	Energy	the ability to do work	28
16303928581	electric charges	are from protons which are positive and electrons which are negative	29
16303928582	Electric charges	Made from protons and protons attracting each other	30
16303928583	law of reflection	the angle of incidence of a wave is always equal to the angle of reflection	31
16303928584	Power	The rate at which work is done	32
16303928585	wave	A repeating movement or disturbance that transfers energy through matter or space	33
16303928586	electricity	Comes from protons and electrons	34
16303928589	Law of Conservation of charge	electric charges can be transferred from object to object, but it cannot be created or destroyed	35
16303928590	static electricity	the accumulation of excess electric charge on an object	36
16303928592	Reflection	occurs when a wave strikes an object or surface and bounces off it	37
16303928593	medium	matter through which a wave travels	38
16303928594	Energy	the ability to do work	39
16303928595	potential energy	Energy that is stored	40
16303928596	Work formula	force x distance	41
16303928597	Mechanical waves	waves that require a medium to travel	42
16303928598	Refraction	the bending of a wave caused by a change in its speed as it moves from one medium to another	43
16303928599	Law of conservation of charge	electric charges can be transferred from object to object, but it cannot be created or destroyed	44
16303928600	Atoms	becomes charged by gaining or losing electrons	45
16303928601	Conductor	A material in which electrons easily flow	46
16303928602	Friction	the force that opposes the sliding motion of 2 touching surfaces	47
16303928603	elastic potential energy	Energy stored by something that can stretch or compress like a rubber bad or a spring	48
16303928605	kinetic energy	Energy in the form of motion	49
16303928606	Insulators	A type of material in which electrons do not easily flow	50
16303928607	Law of conservation of charge	electric charges can be transferred from object to object, but it cannot be created or destroyed	51
16303928608	conductor	A material in which electrons easily flow	52
16303928609	Diffraction	an object causes a wave to change direction and bend toward it	53
16303928610	transverse waves	matter moves back and forth at right angles to direction that waves travel	54
16303928611	compressional wave	matter moves back and forth as the wave travels through it	55
16303928612	Interference	when 2 or more waves overlap and combine to form a new wave	56
16303928613	positive, negative charges	CHARGES EXERT FORCES ON EACH OTHER ;THE LIKE CHARGES REPEL	57
16303928614	Electric current	the net movement of electric charges in a single direction	58
16303928615	Power formula	work/time	59
16303928616	Chemical Potential Energy (CPE)	Energy stored in chemical bonds	60
16303928618	Insulator	A type of material I'm which electrons do not easily flow	61
16303928619	potential energy	Energy that is stored	62
16303928620	rolling friction	friction between a rolling object and the surface it rolls on	63
16303928621	gravitational potential energy	anything that can fall has stored GPE	64
16303928622	Crests	the highest points on a transverse wave	65
16303928623	constructive interference	Resulting wave is bigger	66
16303928624	charging by contact	the process of transferring charge by touching or rubbing	67
16303928625	conductor	a material in which electrons easily flow EXAMPLE: METALS	68
16303928626	voltage difference	the force that causes electric charges to flow; charges flow from high voltage to low voltage	69
16303928627	Troughs	the lowest points on a transverse wave	70
16303928628	destructive interference	Resulting wave is smaller	71
16303928629	charging by induction	the rearrangement of electrons on a neutral object caused by a nearby charged object	72
16303928630	Insulator	A material in which electrons are not able to move easily EXAMPLE: rubber,wood,plastic	73
16303928631	fluid friction	The friction when an object moves through a fluid meaning fluid or gas	74
16303928632	Circuit	a closed path that electric current follows	75
16303928633	machine	A device that makes work easier	76
16303928634	mechanical energy	Total amount of kinetic energy and potential energy	77
16303928635	Compressions	The parts where the coils are close together in a compressional wave	78
16303928636	electromagnetic waves	made by vibrating electric charges and can travel through space	79
16303928637	electric current	the net movement of electric charges in a single direction	80
16303928638	charging by contact	the process of transferring charge by touching or rubbing	81
16303928639	Dry cell battery	chemical reactions occur in a moist paste causing the transfer of electrons	82
16303928640	elastic potential energy	Energy stored by something that can stretch or compress like a rubber bad or a spring	83
16303928641	The law of conservation of energy	energy may change form but it cannot be created or destroyed under ordinary conditions	84
16303928642	air resistant	a friction-like force that opposes motion of object that move through air depend on speed, size and shape	85
16303928643	work	The transfer of energy that occurs when an object moves	86
16303928644	velocity	includes the speed of an object and the direction of its motion	87
16303928645	Input force	The force applied to a machine	88
16303928646	wet cell battery	contains two connected plates made of different metals in a conducting solution	89
16303928647	charging by induction	the rearrangement of electrons on a neutral object caused by a nearby charged objects	90
16303928648	Frequency	number of vibrations per second	91
16303928649	Rarefraction	Less dense region; coils are farther away ; In a compressional wave	92
16303928650	voltage difference	force that causes electric charges to flow; charges flow from high voltage to low voltage	93
16303928651	Frequency	# of complete wavelengths that pass a point in a given time	94
16303928652	Radio waves	Low frequency waves with wave lengths of about 1-10 cm( used for radio stations, microwaves, radars)	95
16303928653	circuit	a closed path that electric current follows	96
16303928654	electric current	the net movement of electric charges in a single direction through a wire or conductor	97
16303928655	Resistance	the tendency for a material to oppose the flow of electrons, changing electrical energy into thermal energy and light	98
16303928656	Chemical Potential Energy (CPE)	Energy stored in chemical bonds	99
16303928657	acceleration	rate of change of velocity	100
16303928658	Infrared waves	Have a slightly higher frequency than radio waves(remote controls, warmth of a fire and satellites)	101
16303928659	Wave formula	v=fλ; wave speed(m/s)= frequency(Hz) *wavelength(m)	102
16303928660	dry cell battery	chemical reactions occur in a moist paste causing transfer of electrons	103
16303928661	voltage difference	related to the force that causes electric charges to flow; measured in volts	104
16303928662	Motion	occurs when an object changes position relative to a reference point	105
16303928663	Ohm's Law	the current in a circuit equals the voltage difference divided by the resistance	106
16303928664	Output force	Force applied by machine	107
16303928665	Amplitude	measure of the energy in a wave	108
16303928666	visible light	the range of electromagnetic waves that you can detect with your eyes	109
16303928667	wet cell battery	contains two connected plates made of different metals in a conducting solution	110
16303928668	circuit	a closed path the electric current follows	111
16303928669	series circuit	An electric circuit with a single path	112
16303928670	gravitational potential energy	anything that can fall has stored GPE	113
16303928671	distance	how far an object has traveled (area between 2 reference points)	114
16303928672	dry cell battery	chemical reactions occur in a moist paste causing a transfer of electrons	115
16303928760		the ratio of the output force to the input force	116
16303928673	parallel circuit	A circuit that contains more than one path for current flow.	117
16303928674	Resistance	the tendency for a material to oppose the flow of electrons, changing electrical energy into thermal energy and light caused by making wires longer and thinner and hotter	118
16303928675	ROYGBIV	red, orange, yellow, green, blue, indigo, violet	119
16303928676	Displacement	the distance and direction of the object's change in position relative to the starting point	120
16303928677	radio transmission	radio converts electromagnetic waves into sound waves	121
16303928678	Ultraviolet waves (UV)	Frequencies slightly higher than visible light( the sun(sunburns, vitamin D production, fluorescent materials absorb)) kill bacteria	122
16303928679	carrier wave	specific frequency	123
16303928680	Ohm's law	Current in a circuit equals voltage difference divided by resistance	124
16303928681	wet cell battery	contains two connected plates made of different metals in a conducting solution	125
16303928682	mechanical energy	Total amount of kinetic energy and potential energy	126
16303928683	speed	The distance an object travels per unit of time(rate of change in position)	127
16303928684	Electric fuse	Small pice of metal that melts if current is too high	128
16303928685	Resistance	the tendency for a material to oppose the flow of electrons, changing electrical energy into thermal energy and light	129
16303928686	machanical advantage formula	output force/input force	130
16303928687	average speed formula	total distance/total time	131
16303928688	X-rays and gamma rays	Ultra-high frequencies that can travel through matter, damage cells( bone images, radiation therapy)	132
16303928689	television	audio is sent by FM radio waves and video is sent by AM radio signals.	133
16303928690	cathode ray tube	Produce images you can see on tv. Surface is covered in spots that flow red, green, or blue when struck by electron beams	134
16303928691	circuit breaker	small piece of metal that bends when it gets hot, opening circuit and stopping current flow	135
16303928692	Resistance	measured in ohms	136
16303928693	The law of conservation of energy	energy may change form but it cannot be created or destroyed under ordinary conditions	137
16303928694	instataneous speed	speed any given point in time	138
16303928761		Measure of how much work is put into a machine is changed into useful output work	139
16303928695	Telephones	electrical signal creates radio wave that is transmitted to and from a microwave tower	140
16303928696	Magnetism	refers to the properties and interactions of magnets in which there is a force of attraction or repulsion between like or unlike poles	141
16303928697	Ohm's Law	the current in a circuit equals the voltage difference divided by the resistance	142
16303928698	average speed	total distance travel divided by total timme	143
16303928699	Magnetic field	exerts a force on other magnets and objects made of magnetic materials	144
16303928700	work	The transfer of energy that occurs when an object moves	145
16303928701	Global Positioning System (GPS)	system of satellites, ground stations and receives that receive high freq microwave signals, amplify it and return it to Earth.	146
16303928702	electric current	measured in amperes	147
16303928703	constant speed	speed that does not vary	148
16303928704	Newton's first law of motion	an object in motion stays in motion or an object rests, until an unbalanced net force acts on it (also law of inertia)	149
16303928705	Simple machine	A machine that does work with only one movement	150
16303928706	series circuit	An electric circuit with a single path	151
16303928707	Magnetic domains	groups of atoms with aligned magnetic poles	152
16303928708	permanent magnet	Made by placing a magnetic material in a strong field , forcing magnet domains to line up	153
16303928709	Lever	A bar that is free to pivot around a fixed point (fulcrum)	154
16303928710	Inertia	The tendency of an object to resist any change in motion	155
16303928711	parallel circuit	A circuit that contains more than one path for current flow.	156
16303928712	Complex Circuit	a circuit composed of both series and parallel circuits	157
16303928713	Electromagnet	a temporary magnet made by wrapping a wire coil carrying a current around an iron core	158
16303928714	1st class lever	fulcrum in the middle	159
16303928715	Newton's Second Law of Motion	a net force acting on an object causes the object to accelerate in the direction of the force	160
16303928716	Force formula	F=ma	161
16303928717	2nd class lever	Output force is between input force and fulcrum ex: wheelbarrow	162
16303928718	Electric motors	a device that converts electrical energy into mechanical energy	163
16303928719	circuit breaker	small piece of metal that bends when it gets hot, opening circuit and stopping current flow of electrons	164
16303928720	Direct Current (DC)	Electric current that flows in only one direction	165
16303928721	Newton's Third Law of Motion	For every action there is an equal and opposite reaction	166
16303928722	3rd class lever	Input force is between output force and fulcrum ex: broom	167
16303928723	electric fuse	small piece of metal that melts if current becomes too high, opening circuit	168
16303928724	momentum	property of moving object resulting from its mass and velocity (momentum=mass *velocity	169
16303928725	Magnetism	refers to the properties and interactions of magnets in which there is a force of attraction or repulsion between like or unlike poles	170
16303928726	Alternate Current (AC)	Reverses the direction of the current flow in regular patterns	171
16303928727	Pulley	A simple machine that consists of a grooved wheel with a rope or cable wrapped around it.	172
16303928728	magnetic field	exerts a force on other magnets and objects made of magnetic materials(strongest closest to the magnet)	173
16303928729	Gravity	any two masses that exert an attractive force on each other	174
16303928730	fixed pulley	attached to something that doesn't move	175
16303928731	weight	the gravitational force exerted on an object, measured in units called newtons	176
16303928732	moveable pulley	A pulley that is NOT attached to a structure	177
16303928733	pole	all magnets have a north a south	178
16303928734	Block and tackle	combines multiple fixed and moveable pulleys	179
16303928735	repel	like poles	180
16303928736	projectile	anything thrown or shot through the air	181
16303928737	attract	unlike poles	182
16303928738	wheel and axle	Consists of an axle attached to the center of a larger wheel so that the wheel and axle rotate together	183
16303928739	horizontal motion	motion parallel to Earth's surface	184
16303928740	inclined plane	a sloping surface, such as a ramp, that reduces the amount of force required to do work	185
16303928741	vertical motion	motion perpendicular to Earth's surface	186
16303928742	magnetic materials	iron, cobalt, nickel	187
16303928743	screw	An inclined plane wrapped around a cylinder	188
16303928744	magnetic domains	groups of atoms with aligned magnetic poles to small to be seen with our eyes	189
16303928745	centripetal acceleration	acceleration toward the center of a curved or circular path	190
16303928746	wedge	an inclined plane with one or two sloping sides	191
16303928747	permanent magnets	are made by placing a magnetic material in a strong magnetic field, forcing magnetic domains to line up	192
16303928748	magnetism and electricity	when electric current flows through a wire , a magnetic field that forms around a wire	193
16303928749	compound machine	2 or more simple machines that operate together	194
16303928750	the amount of current flowing through the wire.	what does the strength of a magnetic field depend on ?	195
16303928751	electromagnet	a temporary magnet made by wrapping a wire coil carrying a current around an iron core	196
16303928752	By adding more turns or coils to the wire coil or increasing the current through the wire	how can you increase the strength of the magnetic field?	197
16303928753	electric motors	a device that converts electrical energy into mechanical energy	198
16303928754	simple electric motor	the electromagnet rotates between the poles of a permanent magnet	199
16303928755	DC current (direct current)	Current flows in one direction only through a wire EXAMPLE: battery	200
16303928756	AC (alternating current)	reverses the direction of the current flow in regular patterns EXAMPLE: PLUGGING A TOASTER INTO A WALL OUTLET	201