Key Terms Flashcards
(182 cards)
1
Q
What is physics?
A
The study of forces, energy, and motion.
2
Q
What is a controlled experiment?
A
An experiment in which a scientist intentionally changes one quantity and observes how another quantity changes.
3
Q
What are variables in an experiment?
A
The changing quantities in an experiment.
4
Q
What is an independent variable?
A
The variable that is changed by the experimenter in an experiment.
5
Q
What is a dependent variable?
A
The variable that changes because of the independent variable.
6
Q
What is a control variable?
A
The variable that scientists do not wish to study that needs to either be eliminated or kept constant.
7
Q
What are observational studies?
A
Experiments in which systems are observed as they appear in nature, and researchers do not attempt to change them.
8
Q
What are field studies?
A
Observational studies done outside a laboratory setting.
9
Q
What are laboratory studies?
A
Experiments that take place in a highly controlled, artificial setting.
10
Q
What is a physical model?
A
A model that represents a real object or a phenomenon, usually on a smaller scale.
11
Q
What is a conceptual model?
A
A model that can be used to visualize things that cannot be seen, such as atoms.
12
Q
What is a mathematical model?
A
A model that describes physical objects or phenomena using mathematical methods.
13
Q
What is a computer model?
A
A model that uses computers to explain and predict complex systems, such as weather patterns and the detailed movements of objects in the solar system.
14
Q
What is direct proportionality?
A
A mathematical relationship between two variables whose ratio remains constant as their numerical values change.
Synonymous with positive correlation.
15
Q
What is inverse proportionality?
A
A mathematical relationship between variables in which an increase in the value of one causes a decrease in the value of the other.
Synonymous with negative correlation.
16
Q
What does no correlation mean?
A
A lack of relationship between variables on a graph; a change in one value does not affect the other.
17
Q
What is a proportionality constant?
A
A parameter that quantifies the relative changes in variables that are directly or inversely proportional.
18
Q
What is the origin of the plot?
A
The point on a graph where the value of both x and y axes are zero.
19
Q
What is a scatterplot?
A
A type of graph comparing two variables as data points in Cartesian, x-y coordinates.
20
Q
What is a ratio?
A
A quantity that compares the values of two variables expressed as a fraction.
21
Q
What does density depend on?
A
Density depends on the material itself, not on the object’s size or mass.
22
Q
What is molar mass?
A
A derived unit specifying the number of grams of a substance per mole of that substance.
23
Q
What are molar units?
A
The number of moles of a particular particle or molecule in one liter of another substance.
24
Q
How is speed defined?
A
Defined as the distance traveled per time interval.
25
What is volume?
The amount of space an object occupies.
26
What is velocity?
An object's speed and direction.
27
What is acceleration?
The rate at which the velocity of an object changes with respect to time.
28
What is force?
A push or a pull.
29
What are balanced forces?
Forces that combine to produce a net force of zero.
30
What is zero net force?
There is no net force and therefore no acceleration.
31
What is non-zero net force?
There is a net force, so acceleration is possible.
32
What is a hypothesis?
A testable statement about how something in nature works.
33
What is a law in science?
A concise statement that is supported by scientific evidence and repeated experiments and describes a widespread pattern in nature.
34
What is a theory?
A statement that explains a wide range of observations and that is supported by a large body of scientific evidence.
35
What does Newton's first law state?
The net force on an object is the cause of its acceleration.
36
What is inertia?
The tendency to keep the same motion, to remain at rest, or to maintain the same velocity.
37
What does Newton's second law state?
The acceleration of an object depends on the mass of the object and the amount of force applied.
38
What does Newton's third law state?
Whenever one object exerts a force on a second object, the second object exerts a force of the same magnitude in the opposite direction on the first object.
39
What is friction?
The force that opposes the motion of an object on which it acts.
40
What is kinetic friction?
Kinetic (moving) friction is the force of friction between two objects moving against each other.
41
What is static friction?
Static (stationary) friction occurs between two objects touching each other but not moving against each other.
42
What is gravity?
An attractive force that acts to pull objects closer to each other.
43
What is linear momentum?
The mass of an object times its velocity.
44
What is the law of conservation of momentum?
A scientific law that states that momentum is conserved when two or more objects collide.
45
What is an elastic collision?
A collision where the total momentum and total kinetic energy are conserved.
46
What is an inelastic collision?
A collision where the total momentum is conserved but the total kinetic energy is not conserved.
47
What is work?
Energy that is being used or converted; results in the displacement of an object in the direction of an applied force.
48
What is energy?
The capacity to do work or to cause change.
49
What is kinetic energy?
Energy objects have because they are moving.
50
What is potential energy?
Energy that is stored by an object.
51
What is gravitational potential energy?
Energy that an object has due to its height above the ground.
52
What is chemical potential energy?
Energy that is stored in the chemical bonds in a substance.
53
What is elastic potential energy?
Energy that is stored in stretched springs, rubber bands, and similar objects.
54
What is electromagnetic energy?
Sometimes called light energy, this is energy that is carried by electromagnetic waves.
55
What is thermal energy?
Energy produced by the motions of atoms and molecules resulting in an increase in temperature.
56
What is the law of conservation of energy?
The law explaining that energy cannot be created or destroyed; it can only be transferred or converted from one form to another.
57
What is oscillation?
A repetitive motion that usually occurs about a center point.
58
What is an electromagnetic wave?
A combination of an oscillating electric field and an oscillating magnetic field; electromagnetic waves can travel through both the vacuum of space and a medium.
59
What is equilibrium?
A position or state to which an oscillating object eventually returns after a disturbance is gone.
60
What are mechanical waves?
Waves that can travel only through matter and require a medium to transport their energy.
61
What is a vacuum?
A space in which there is no matter.
62
What is a transverse wave?
A wave where the oscillation is perpendicular to the direction the wave is traveling.
63
What is a longitudinal wave?
A wave where the oscillation is parallel to the direction the wave is traveling.
64
What is the equilibrium position?
The center point of a wave where no movement is occurring.
65
What is a crest?
The highest point of a transverse wave.
66
What is amplitude?
Vertical distance from the equilibrium to the crest or the equilibrium to the trough of a transverse wave.
67
What is wavelength?
The horizontal distance after which the wave repeats itself in space.
68
What is period?
An interval in time after which the motion of a particle on the medium starts to repeat.
69
What is frequency?
The number of oscillations the wave makes in a given amount of time, typically a second.
70
What is a trough?
The lowest point of a transverse wave.
71
What is visible light?
A very small portion of the EM spectrum, including all of the wavelengths of light that the average unaided human eye can detect.
72
What are radio waves?
Waves with the longest wavelength, the lowest frequencies, and lowest energies of all types of EM radiation.
73
What are microwaves?
Waves with higher frequencies and energies than radio waves but lower than those of infrared radiation.
74
What are infrared (IR) waves?
Waves with higher frequencies than those of microwaves but lower than those of visible light.
75
What are ultraviolet (UV) waves?
Waves with wavelengths that are just shorter than those of visible violet light but longer than those of X-rays.
76
What are X-rays?
Waves with wavelengths that are shorter than UV rays but longer than gamma rays.
77
What are gamma rays?
Waves with the shortest wavelengths and the highest frequencies and energies of all EM radiation.
78
What are radio waves used for?
Produced naturally by lightning and by certain kinds of stars and galaxies; used for communication.
79
What are microwaves used for?
Used in food preparation, communication, and radar systems.
80
What is infrared radiation used for?
Used to detect heat sources or to generate heat.
81
What is visible light used for?
Used in laser applications and in photosynthesis.
82
What is ultraviolet (UV) radiation used for?
Used to detect counterfeit bills and documents; can cause skin cancer.
83
What are X-rays used for?
Used to take images of the inside of the body.
84
What are gamma rays used for?
Used to treat cancer and to detect people or dangerous objects behind thick metal walls.
85
What is compression?
When particles of matter are pushed closer together.
86
What is expansion?
When particles of matter are pulled away from each other.
87
What is pitch?
How high or low a sound is; the pitch of a sound depends on the frequency of the sound waves.
88
What is loudness?
The energy of a sound wave; the greater the energy of the wave, the greater its amplitude and, therefore, the louder the sound.
89
What is an atom?
The basic building blocks of matter consisting of a nucleus (made of protons and neutrons), and electrons surrounding the nucleus.
90
What is an electron?
A negatively charged subatomic particle found outside of the nucleus.
91
What is energy?
The capacity to cause change or do work.
92
What is mass?
A measure of how much matter an object has.
93
What is matter?
Anything that takes up space and has mass.
94
What is a nucleus?
The center of an atom where the protons and neutrons are located.
95
What is a neutron?
A neutral (not charged) subatomic particle; one of the two particles that make up an atomic nucleus.
96
What is a proton?
A positively charged subatomic particle; one of the two particles that make up an atomic nucleus.
97
What is an electron cloud?
A diffuse region of negative charge surrounding an atomic nucleus; it describes the region in which electrons are located (their exact location is uncertain).
98
What are valence electrons?
Electrons that occupy the outermost regions, those farthest from the nucleus of an atom.
99
What is an element?
A substance that is composed of a single type of atom, as defined by the number of protons in the nucleus.
100
What is a compound?
A chemical that contains at least two different types of atoms in a fixed ratio.
101
What is a chemical?
Any substance that has a definite, fixed chemical composition.
102
What are chemical bonds?
Attractive forces that hold atoms together.
103
What is a molecule?
An exact number of atoms of one type of element or more than one type of element that are held together by covalent bonds.
104
What is an organic compound?
A compound that contains carbon and hydrogen.
105
What is a heterogeneous mixture?
Components that are not evenly mixed.
106
What is a homogeneous mixture?
Components that are evenly mixed and cannot be differentiated with the unaided eye.
107
What is a pure substance?
A chemical that contains only one type of element or compound (also referred to as a 'substance').
108
What is a mixture?
A combination of two or more pure substances.
109
What is volume?
The amount of space that a substance or object occupies.
110
What are macroscopic properties?
Properties that are visible to the naked eye.
111
What are microscopic properties?
Properties that are too small to see without using a microscope.
112
What characterizes a solid?
Particles that have relatively little energy and tend to vibrate about a fixed position.
113
What characterizes a liquid?
Particles that have a bit more energy so they are able to slide past one another, and thus be poured.
114
What characterizes a gas?
Particles that have a lot of energy and move very quickly, thus they are spread far apart.
115
What is a chemical change?
A chemical change occurs when a change in chemical composition takes place.
116
What is a chemical reaction?
A chemical reaction is a process where chemical bonds are formed or broken.
117
What is a physical change?
A physical change is when matter changes in appearance without changing in chemical composition.
118
What are products in a chemical reaction?
Products are the new substances formed by a reaction.
119
What are reactants in a chemical reaction?
Reactants are substances that go into a chemical reaction.
120
What is an ion?
An ion is an atom with a net electric charge.
121
What is an ionic bond?
An ionic bond is a strong attractive force between two ions, where one is positively charged and the other is negatively charged, leading to attraction between the unlike charges.
122
What is a covalent bond?
A covalent bond occurs when two nonmetals react and share electrons, providing the attractive force that holds the atoms together.
123
What is a metallic bond?
A metallic bond is formed when metal atoms are bonded, allowing valence electrons to move freely from one metal atom to another.
124
What is a period?
A period is the rows in the periodic table.
125
What is a group?
A group is the columns in a periodic table.
126
What is a family?
A family is the elements within a group that have the same number of valence electrons.
## Footnote
Because elements within a group have the same number of valence electrons, they tend to react similarly and are considered part of the same family.
126
What are metals?
Metals are atoms that tend to lose electrons.
127
What are nonmetals?
Nonmetals are atoms that have electrons that are very tightly associated with the nucleus.
128
What are metalloids?
Metalloids are atoms that are shiny like metals but have an intermediate electrical conductivity; known as semiconductors.
129
What is the law of conservation of mass?
The law of conservation of mass is a scientific law that states matter cannot be created or destroyed.
130
What are coefficients?
Coefficients indicate the ratio of chemicals that participate in a reaction; the coefficient is written before the chemical formula; no coefficient indicates a ratio of one.
131
What are subscripts?
Subscripts (the number written below the line) indicate the ratio of atoms in a compound; no subscript indicates that only one of the atoms is present.
132
What is temperature?
Temperature is a measure of the average kinetic energy per particle.
133
What is heat?
Heat is the thermal energy that is transferred from one substance to another.
134
What is thermal energy?
Thermal energy is the total kinetic energy of all the particles that make up the gas.
135
What is evaporation?
Evaporation is the process by which a liquid turns into a gas.
136
What is condensation?
Condensation is a process that occurs when particles in the gas phase no longer have sufficient energy to overcome attractive forces between them and turn into liquid.
137
What is a phase change?
A phase change is a change from one state to another.
138
What is melting?
Melting is the process of turning from a solid into a liquid.
139
What is freezing?
Freezing is the process that occurs when a liquid turns into a solid.
140
What is earth science?
Earth science is the study of Earth's structure and composition, as well as the processes that change Earth.
141
What is the universal law of gravitation?
The universal law of gravitation is that the gravitational force of attraction between any two objects is proportional to the product of their masses and inversely proportional to the distance between them.
142
What is a nuclear fusion?
Nuclear fusion is a process that occurs when hydrogen and other small nuclei fuse to form larger nuclei, releasing large amounts of energy in the process.
143
What is a star?
A star is a celestial body that is held together by its own gravity and that releases visible light and other forms of radiant energy generated by nuclear fusion.
144
What is a galaxy?
A galaxy is a collection of hundreds of billions of stars that clustered together by gravity.
145
What is a orbit?
An orbit is when gravity causes one celestial body to move around another in a nearly circular path.
146
What is a solar system?
A solar system is the collection of objects that orbit a star.
147
What is a planet?
A planet is a large, spherical object that orbits a star.
148
What is a moon?
A moon is a naturally formed object that orbits a planet.
149
What are asteroids?
Asteroids are very small, rocky bodies that orbit the sun.
150
What are comets?
Comets are relatively small, icy, dusty bodies that travel around the sun in very elliptical orbits.
151
What is the axis of rotation?
The axis of rotation is the imaginary line from the North Pole to the South Pole on which a planet rotates.
152
What is crust?
The crust is the outermost rocky shell at the surface of Earth.
153
What is the mantle?
The mantle is the rocky layer beneath the crust, and the thickest layer of the Earth.
154
What is the outer core?
The outer core is the metallic outside layer of the Earth's core that is mainly composed of hot iron in a liquid state.
155
What is the inner core?
The inner core is the metallic inside layer of Earth's core that is composed of a solid ball of nickel-iron alloy under extreme pressure.
156
What is weathering?
Weathering is the alteration or breakdown of rock or soil.
157
What is physical weathering?
Physical weathering is weathering that results from mechanical processes such as changes in temperature or pressure.
158
What is chemical weathering?
Chemical weathering is weathering that is the result of chemical processes or reactions that cause a rock's composition to change.
159
What is deposition?
Deposition is the process by which soil, sediment, or rocks are added to a landform.
160
What is erosion?
Erosion is the mechanism responsible for the transportation or removal of material.
161
What is a glacier?
A glacier is a slowly moving mass of ice formed by the accumulation and compaction of snow.
162
What are sand dunes?
Sand dunes are an example of the aeolian process requiring the same three basic elements for formation: a large quantity of loose and unvegetated sand, wind, and an obstacle.
163
What are meanders?
Meanders are curves in a river that form as the outer bank of a river erodes while the inner edge is deposited with sediment.
164
What are river valleys?
River valleys are valleys produced by erosion that form when a river cuts down into the underlying bedrock in a steep V shape.
165
What is a mineral?
A mineral is a naturally occurring, solid, inorganic element or compound that is formed by natural processes, has a limited range of possible chemical composition, and has a definite arrangement of atoms.
166
What is a rock?
A rock is a heterogeneous mixture of one or more minerals.
167
What are sedimentary rocks?
Sedimentary rocks are rocks made up of weathered particles, such as sand, silt, clay, gravel, cobbles, or even occasionally boulders, that have been cemented together into hard rock.
168
What are igneous rocks?
Igneous rocks are formed by lava or magma, molten rock, or lava, that cools quickly into rock when it erupts onto Earth's surface.
169
What are metamorphic rocks?
Metamorphic rocks are rocks that have been changed from their original form and typically occur when a rock is partially buried and exposed to elevated temperatures and pressures that are not extreme enough to melt the rock completely.
170
What is a rock cycle?
A rock cycle is the various processes that change rocks from one form to another.
171
What is analog?
Analog is a close approximation, or direct analogy, of the long-term behavior of materials and processes found in a geologic feature.
172
What is a principle of superposition?
The principle of superposition is a principle stating that in any sequence of undeformed sedimentary rocks, each bed is younger than the one below it and older than the one above it.
173
What is the principle of crosscutting relationships?
The principle of crosscutting relationships is a principle used to determine the relative ages of different rocks: if a rock, fault, or other feature cuts through a rock layer, that rock layer must have been preexisting in order to have been cut through.
174
What is an unconformity?
An unconformity is a buried erosional surface.
175
What is a fossil?
A fossil is the remains or traces of animals, plants, or other organisms that have been preserved within sedimentary rocks.
176
What is an earthquake?
An earthquake is a sudden shaking of the ground that occurs when rocks in Earth's crust break suddenly, releasing energy.
177
What is a volcano?
A volcano is an opening in Earth's crust through which molten rock and gases erupt on Earth's surface.
178
What is a convergent boundary?
A convergent boundary is a plate boundary defined by the plates pushing into one another.
179
What is a divergent boundary?
A divergent boundary is a plate boundary defined by the plates moving apart from one another.
180
What is a transform boundary?
A transform boundary is a plate boundary defined by each plate grinding past one another.
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