Definitions Flashcards
(312 cards)
1
Q
Abberation
A
Visual alterations as the result of an imperfect optical device; maybe chromatic or spherical.
2
Q
Absolute pressure
A
The actual pressure at a given depth in a fluid, including both ambient pressure at the surface and the pressure associated with increased depth in the fluid; also called hydrostatic pressure.
3
Q
Absolute zero
A
The theoretically cold-est temperature at which all atomic movements would halt (0 K).
4
Q
Acceleration
A
The rate ofchange in the velocity of an object; related to force through mass and measured in m/s2.
5
Q
Accuracy
A
The tendency for data tc represent the true answer; also known as validity.
6
Q
Adhesion
A
The intermolecular force between molecules of a liquid and molecules of another substance.
7
Q
Adiabatic
A
A thermodynamic process that occurs with no heat exchange.
8
Q
Air resistance
A
The resistance which opposes the motion of a falling object.
9
Q
Algebraic system
A
A method for determining the values of variables that are the same in two or more equations by relating them to each other.
10
Q
alpha particle
A
A helium nucleus (4/2 He) emitted during alpha decay.
11
Q
Alternating current (AC)
A
ln circuits. a pattern of current flow which changes direction periodically.
12
Q
Ammeter
A
A device used to measure current within a circuit.
13
Q
Amplitude
A
The maximum displacement from the equilibrium point during wave or oscillatory motion.
14
Q
Antinode
A
A point of maximum displacement in a standing wave.
15
Q
Archimedes’ principle
A
States that a body immersed in a volume of fluid experiences a buoyant force equal to the weight of the displaced fluid.
16
Q
Atomic absorption
A
Process in which an electron jumps from a lower to a higher energy orbit by absorbing a photon of light.
17
Q
Atomic emission
A
Process by which an electron falls from a higher to a lower energy level and emits a photon of light.
18
Q
Atomic number
A
The number ofprotons in the nucleus of a given element.
19
Q
Attenuation
A
The loss of energy of a propagating wave as a result of nonconservative forces; also known as damping.
20
Q
Autonomy
A
The ethical principle that states that individuals have the right to make decisions about their own healthcare.
21
Q
Beat frequency
A
The difference between the frequencies of two interacting sound waves.
22
Q
Beneficence
A
The ethical principle that states that practitioners should always act in their patients’ best interests; in research ethics, also states that a research project should create a net positive change for both the study population and general population.
23
Q
Beta particle
A
An electron emitted during B-decay, or a positron emitted during B+ decay.
24
Q
Bernoulli’s equation
A
An equation that relates static and dynamic pressure for a fluid to the pressure exerted on the walls of a tube and the speed of the fluid.
25
Bias
A result of flaws in the data collection phase of an experimental or observational study that typically skews data within a study.
26
Bimodal distribution
A distribution of data with two peaks and a valley in between them.
27
Blackbody
An ideal absorber of all wavelengths of light.
28
Blinding
Withholding information about a research subject's group assignment from the subject or evaluator to remove some potential bias from the results.
29
Boiling point
The temperature at which the vapor pressure of a liquid equals the ambient (incident) pressure, usually atmospheric pressure; the temperature at which the liquid boils.
30
Boundary layer
A region of laminar flow in an otherwise turbulent system that occurs at the very edges of the vessel
31
Box-and-whisker plot
A visual representation of the range of data, quartiles, and the interquartile range; may contain outliers as separate points.
32
Buoyancy
The upward force that results from immersion in a fluid; described by Archimedes' principle.
33
Capacitance
A measure of the ability of a capacitor to store charge; the magnitude of the charge on one plate divided by the potential difference between the plates; measured in farads (F).
34
Capacitor
Two conducting surfaces that store charges of equal magnitude but opposite sign when connected to a voltage source.
35
Case-control study
An observational study that starts by identifying subjects with a given outcome, then looks for correlations to specific exposures within the group.
36
Causation
A relationship between two variables in which one (at least partially) depends on the other in order to occur.
37
Center of gravity
A point such that the entire force of gravity acting on an object can be thought of as acting at that point.
38
Center of mass
The point that acts as if the entire mass of an object was concentrated at that point.
39
Centripetal acceleration
The acceleration of an object that travels in a circle; it is always directed toward the center of the circle if the object is in
uniform circular motion.
40
Centripetal force
The force responsible for centripetal acceleration; usually a result of gravity, tension, or a normal force.
41
Charges
Entities that can influence the environment through electrostatic forces or be influenced by electrostatic forces, measured in coulombs (C).
42
Chromatic aberration
A dispersive effect within a spherical lens.
43
Circular motion
A form of motion that occurs when forces cause an object to move in a circular.
44
Cohesion
The intermolecular forces experienced between the molecules of a liquid.
45
Cohort study
An observational study in which subjects are sorted into groups based on different exposures, and then assessed at various intervals to determine outcome.
46
Concave
A surface that has a similar curvature to the interior of a sphere.
47
Condensation
The phase transition from a gas to a liquid.
48
Conductance
In the transfer of charge, the degree to which an object conducts electricity. Conductance can be metallic or electrolytic.
49
Conduction
In thermodynamics, the transfer of heat by physical motion of a fluid over a material.
50
Conduction pathway
A route for current to take through a resistor.
51
Conductor
A material that allows the free movement of electrical charge; one with very low or zero resistance.
52
Confidence
A statistical indicator of the likelihood that acquired results did not occur by random chance; equal to 1 - alpha.
53
Confounding
An error that results when a causal variable is associated with two other variables in a study but is not accounted for; may falsely indicate that the two variables are associated.
54
Conservative force
A force that does not cause energy to be dissipated from a system, such as gravity, electrostatic forces, and springs (approximately conservative); pathway independent and associated with a potential energy function.
55
Control
A set of experimental condi- tions meant to ensure that the results of the experimental group are a result of the intervention.
56
Convection
Heat transfer as a result of bulk flow of a fluid over an object.
57
Converging
The tendency to move parallel light rays toward one another; concave mirrors and convex lenses converge parallel light to a focal point.
58
Correlation
The degree to which two variables have a relationship with one another.
59
Correlation coefficient
A numerical valuebetween -1 and +1 that indicates how strong a relationship
is between two variables.
60
Coulomb's law
Relates the eclectrostatic force between two charged particles to their charges and the distance between them.
61
Critical angle
The angle above which any incident light will undergo total internal reflection; occurs when light is moving from a material with a higher refractive index to one with a lower refractive index.
62
Critical speed
The speed above which flow of a fluid will be turbulent.
63
Cross-sectional study
An observational study in which patients are categorized into different groups at the same point in time.
64
Current
The orderly movement of charge, often in a circuit; measured r by convention as the direction that positive charge would flow within the circuit, and measured in amperes (A).
65
Decay constant
The proportionality constant between the rate at which ra- dioactive nuclei decay and the number of radioactive nuclei remaining.
66
Density
A measure of mass per unit
volume; useful for buoyancy calcula-
tions and usually measured in g/cm3....or kg/m3...or g/mL.
67
Dependent variable
The measured or observed variable in an experiment that is affected by manipulations of the independent variable.
68
Detection bias
An error in data col- lection that results from the tendency to look more carefully for certain outcomes because a known association with that outcome exists.
69
Diamagnetic material
A material made of atoms with no unpaired electrons that have no net magnetic field.
70
Dielectric material
An insulating material used to increase capacitance.
71
Diffraction
The spreading or bending of light rays.
72
Dipole moment
In electrostatics calculations, the product of charge and separation distance.
73
Direct current (DC)
ln circuits, a pattern of current in which charge flows in only one direction.
74
Direct relationships
A relationship in which increasing one variable proportionately increases the other.
75
Dispersion
The separation of light into its component wavelengths when passing through a medium, such as a prism.
76
Displacement
The vector representing the straight-line distance and direction from an initial point; not necessarily equal to total distance traveled, and measured in meters.
77
Diverging
The tendency to move parallel light rays away from one another; convex mirrors and concave lenses diverge parallel light rays from a focal point.
78
Doppler effect
Quantifies the perceived change in frequency of sound due to relative movement between the source and detector (observer).
79
Doppler effect
Quantifies the perceived change in frequency of sound due to relative movement between the source and detector (observer).
80
Double-blind experiment
Experiment in which both the assessor and the subject do not know the subject's group.
81
Dynamics
In kinematics and dynamics, the study of forces and torques.
82
Efficiency
In machines, the ratio of useful work output compared to work input.
83
Electric dipole
A separation of equal and opposite charge by a small distance; can be seen in polar molecules.
84
Electric field
A region generated
by an electric charge or multiple charges that can exert a force on another charge brought into the field;
measured in N/C.
85
Electric meters
Devices used to measure circuit quantities like current, potential difference, or resistance.
86
Electric potential
A measure of electric potential energy per unit charge, given in volts (V); differenc- es in electric potential (voltage) also drive current as the electromotive force in a circuit.
87
Electric potential energy
A form of potential energy that is dependent on the relative position of one charge with respect to another charge or to a collection of charges.
88
Electromagnetic radiation
A form of energy composed of oscillating electric and magnetic fields perpendicular to each other and perpendicul ar to the direction of propagation; includes visible light and other types of trans- verse waves, and can travel through a vacuum.
89
Electromagnetic spectrum
The full range of frequencies and wavelengths of electromagnetic waves.
90
Electromotive force
The difference in electric potential (voltage) that drives current in a circuit or battery.
91
Electron
A subatomic particle that remains outside the nucleus and carries a single negative charge.
92
Electron capture
A process in which an unstable atom absorbs an inner electron that combines with a proton to form a neutron, while releasing a neutrino.
93
Electrostatics
The study of stationary charges and the forces that are created by (and act upon) these charges.
94
Energy
The capacity to do work or transfer heat, measured in joules (J).
95
Entropy
A statistical. measure of the distribution of unusable energy or heat; randomness introduced to a system, measure in J/g*K.
96
Equilibrium
The state at which the net torque or net force is equal to zero; such that there is no acceleration.
97
Equipoise
The state of not knowing whether there is a difference between two interventions; ethically necessary for comparative study of the interventions.
98
Equipotential lines
Regions within an electric field with equal electric potential; movement from one point on these lines to another causes no change in the energy of the system.
99
Excited state
Describes an atom in which an electron occupies an energy state above the minimum energy (ground) state.
100
Exhaustive
Describes a set of outcomes that leave no room for other possible outcomes.
101
External validity
The ability to apply findings of a research study to other populations; also called generalizability.
102
Ferromagnetic material
A material made of atoms with unpaired electrons and become strongly magnetized when exposed to an external magnetic field.
103
Field line
A visual representation of the electric field; points to the direction a force would be exerted on a positive test charge in the electric field.
104
FINER method
A way to determine the usefulness of a research question on the basis of feasibility, interest, novelty, ethics, and relevance.
105
Fission
The splitting of a large nucleus into smaller nuclei with the release ofenergy.
106
Flow rate
The volume per unit time of a fluid in motion.
107
Fluid
A material that conforms to the shape of its container and that can flow.
108
Fluid dynamics
The study of fluids in motion.
109
Fluorescence
A process in which the electrons of certain substances are excited to higher energy levels by high-frequency photons, and then
emit visible light as the energy is released in two or more steps back to the ground state.
110
Focal length
The distance from a mirror or lens to the focal point.
111
Focal point
The point at which rays of light parallel to the axis of a mirror or lens converge, or from which they appear to diverge when reflected by a mirror or refracted by a lens.
112
Force
A push or a pull, measured in newtons (N).
113
Free fall
A system in which the only force is gravity.
114
Freezing
The phase transition from liquid to solid; also called solidification.
115
Frequency
The rate at which a recurring event occurs; usually measured in hertz (Hz).
116
Friction
A nonconservative force that arises from the interactions between two surfaces in contact.
117
Fundamental frequency
The first harmonic of a pipe, string, or other standing wave.
118
Fusion
The merging of small nuclei into a larger nucleus with the release of energy.
119
Gamma rays
High-energy photons released during gamma decay; part of the electromagnetic spectrum.
120
Gauge pressure
ressure above and beyond atmospheric pressure.
121
Gravitational potential energy
A form of potential energy dependent on the relative position an object within a
gravitational field.
122
Gravity
An attractive force between two objects that depends on their masses and the distance between them.
123
Ground
A means of returning charge to the earth.
124
Ground state
The lowest energy state of an atom.
125
Half-life
The amount of time it takes for one-half of a sample of radioactive nuclei to decay.
126
Harmonic series
The set of frequencies that can create standing waves in a given pipe or string.
127
Hawthorne effect
The tendency for research participants to change their behavior because they know they are being observed.
128
Heat
The transfer of thermai energy, measured in joules (J), calories (cal), or kilocalories (kcal or Cal).
129
Heat of transformation
The amount of heat necessary to cause a phase transition of a unit mass of a substance at the characteristic temperature and pressure of that phase transition; also
called latent heat.
130
Hill's criteria
A systematized way of evaluating evidence for causality; only temporality is absolutely necessary to demonstrate causality.
131
Histogram
A visual represenation for numerical data; related to a bar chart.
132
Hydraulic system
A simple machine that exerts mechanical advantage using an incompressible fluid; based on Pascal's principle and conservation of energy.
133
Hydrostatics
The study of fluid systems at rest.
134
Hyperopia
Farsightedness, or the ability to see distant objects while nearby objects are unfocused or blurry.
135
Hypothesis testing
A statistical method used to compare results between groups or to a theoretical value with a given level ofconfidence.
136
Image
The region where light rays converge or appear to converge after being reflected from a mirror or passing through a lens.
137
Independent variable
The manipulated variable in an experiment that affects measurements or observations of the dependent variable.
138
Index of refraction
A ratio of the speed of light in a vacuum to the speed of light in a given medium.
139
Intertia
An object's resistance to a change in its motion when a force is applied.
140
Informed consent
An ethical requirement for treatments or research, which requires that the patient or participant is able to understand the procedure and its consequences and alternatives; related to autonomy.
141
Infrared
A region of the electromagnet ic spectrum that is not visible: may be perceived as heat.
142
Infrasoic
Sound that has a frequency that is lower than the range of human hearing.
143
Insulator
A material that resists the movement of charge because the electrons are tightly associated with their nuclei.
144
Intensity
The average rate of energy expenditure (power) per un it area, measured in W/m2; in waves, intensity is related to the amplitude of the wave.
145
Interference
Interactions between waves traveling in the same space; may be constructive (waves adding together), destructive (waves cancel- ling each other), partially constructive, or partially destructive.
146
Internal validity
The ability to infer causality from a study or to replicate its results under the same conditions.
147
Interquartile range
A measure of distribution of a sample; outliers lie at least 1.5 interquartile ranges below Q1 or above Q3.
148
Inveerse relationship
A relationship in which an increase in one variable is associated with a proportional decrease in the other.
149
Inverted
Describes an image that is upside down relative to the object; in single-mirror or single-lens systems, inverted images are always real.
150
Irreversible
A thermodynamic process that is extraordinarily unfavorable in reverse, usually as a result of changes in entropy.
151
Isobaric
A thermodynamic process that occurs under constant pressure.
152
Isothermal
A thermodynamic process that occurs under constant temperature.
153
Isotopes
Atoms of a given element with different numbers of neutrons and therefore different mass numbers.
154
Isovolumetric
A thermodynamic process that occurs under constant volume; also called isochoric.
155
Justice
The ethical principle that states that practitioners should fairly distrib- ute healthcare resources, and which requires that differences in treatment choices between individuals are only due to morally relevant differences.
156
Kinetic energy
The energy of movement, which depends on both mass and speed; measured in joules (J).
157
Kinetic friction
The friction that exists between a sliding object and the surface over which the object slides.
158
Kirchhoff's laws
Rules that describe the conservation of charge and comervation of energy within an electric circuit; includes the junction rule and loop rule.
159
Laminar flow
Smooth flow within a fluid; characterized by streamlines that do not cross each other and an absence of backwards movement.
160
Lenses
Devices that act to create an image by refracting light; usually have spherical surfaces.
161
Logarithm
The inverse function of exponentiation; logarithmic scales are often used to mask large absolute differences between quantities by presenting them as small scale differences.
162
Longitudinal wave
A wave in which the oscillation of the material is parallel to the direction of propagation; sound is a classic example.
163
Lorentz force
The sum of the electrostatic and magnetic forces acting on a charge.
164
Loudness
Perceived intensity of a sound, which correlates with sound level; measured in decibels (dB).
165
Magnetic field
Field created by a moving charge.
166
Magnetic force
A force which is exerted when a charge moves in a magnetic field, provided the charge has a perpendicular component of velocity in comparison to the magnetic field vector.
167
Magnification
Apparent increase or decrease in size of an image as a result of forming the image with a converging or diverging system.
168
Mass
A measure of the amount of "stuff" in an object; measured in kilograms.
169
Mass defect
The difference between the sum of the masses of unbound nucleons forming a nucleus and the mass of that nucleus in the bound state.
170
Mass number
The sum of the number of protons and neutrons in an atom; also called the atomic mass.
171
Mean
The average of a group of data; specifically, the arithmetic mean.
172
Measures of central tendency
Measures that describe the middle of a sample.
173
Mechanical advantage
The reduction in input force required to accomplish a desired amount of output work using a simple machine.
174
Median
The central value of a data set.
175
Melting
The phase transition from solid to liquid; also known as fusion.
176
Metric system
A system of measurements based on the powers of ten; most commonly used in scientific disciplines.
177
Microwaves
Long-wavelength electromagnetic radiation capable of inducing vibration in bonds.
178
Mode
The most common data point in a data set.
179
Monochromatic
Electromagnetic radiation wherein the wavelength is the same for all incident photons.
180
Mutually exclusive
Describes outcome that cannot occur simultaneously.
181
Myopia
Nearsightedness, or the ability to see nearby objects while distant objects are unfocused or blurry.
182
Natural frequency
The frequency at which a system resonates; also called the resonant frequency.
183
Natural process
In thermodynamics, a process which would occur as expected in nature.
184
Newton's first law
The first law, also called the law of inertia, states that an object will remain at rest or move with a constant velocity if there is
no net force on the object. This law thus accounts for the conservation of mechanical energy.
185
Newton's second law
This law states that any acceleration is the result of the sum of the forces acting on the object and its mass.
186
Newton's third law
This law states that any two objects interacting with one another experience equal and opposite forces as a result of their interaction.
187
Node
A point of zero displacement of a standing wave.
188
Nonconservative force
A force that causes energy to be dissipated from a system, such as friction, air resistance, and viscous drag; pathway dependent.
189
Nonmaleficence
The ethical principle that states that practitioners have an obligation to avoid treatments or interventions in which the potential for harm is greater than the potential for good.
190
Normal
A line perpendicular to the surface of interest.
191
Normal force
The force that two surfaces in contact exert on each other that is perpendicular to the plane of contact.
192
Nucleon
A proton or neutron.
193
Null hypothesis
The hypothesis of no difference; given enough statistical evidence, the null hypothesis may be rejected.
194
Observational study
A study that looks for the connection between exposures and outcomes without demonstrating causality.
195
Ohmmeter
A device used to measure resistance.
196
Ohm's law
Relates voltage, current, and resistance for a given circuit element.
197
Outlier
A data point that deviates
sificantly from the perceived pattern of distribution; depending on the context, an outlier may be disregarded, analyzed normally, or given disproportionate weight when calculating statistics.
198
Parallel
An arrangement of circuit elements in which the current can go through one element or the other, but not through both.
199
Paramagnetic material
A material made of atoms with unpaired electrons that will become weakly magnetized in the presence of an external magnetic field.
200
Parameter
A measure of population data.
201
Pascal's principle
States that pressure applied to a noncompressible fluid is distributed equally to all points within that fluid and the walls of the container.
202
Period
The amount of time it takes for a wave or oscillation to complete one cycle, measured in seconds; the inverse of frequency.
203
Phase difference
The difference in phase between waves with the same frequency, referenced at the same point.
204
Photoelectric effect
A phenomenon in which light of sufficiently
high frequency incident on a metal
in a vacuum causes the metal to emit electrons.
205
Pitch
A perception of sound that results from its frequency; as frequency increases, pitch gets higher.
206
Pitot tubes
Measurement devices for pressure or flow rate of a dynamic fluid system.
207
Plane mirrors
Reflecting surfaces with an infinite radius of curvature, which results in equal image and object distances.
208
Plane-polarized light
Electromagnetic radiation in which all of the electric field vectors are oriented parallel to one another.
209
Poiseuille's law
Relates viscosity, tube dimensions, and pressure differentials to the rate of flow between two points in a system.
210
Population
The group of all individuals who have certain desired characteristics.
211
Positron
Antiparticle of an electron; it has the same mass as an electron and the opposite charge (e+ or B+).
212
Potential difference
The difference of d ectric potential between two distinct points, measured in volts (V); also calk d voltage.
213
Potential energy
Energy associated with position, measured in joules (J); includes gravitational, elastic, chemical, and electrical forms.
214
Power
Rate at which work is accomplished, or energy expenditure per unit time; measured in watts (W). In statistics, the probability
of correctly rejecting a false null hypothesis.
215
Precision
The tendency of measurements to agree with one another; also called reliability.
216
Pressure
The ratio of force to the area over which it is applied; measured in pascals (Pa), millimeters of mercury (mmHg) or torr, or atmospheres (atm).
217
Principle of superposition
When waves interact with each other,
| the displacement of the resultant wave at any point is the sum of the displacements of the two interacting waves.
218
Process functions
Physical quantities that depend on the path taken to get from one state to another; include work and heat.
219
Propagation
In waves and sound, the movement of a wave.
220
Proton
A subatomic particle that carries a single positive charge and has a mass slightly less than 1 amu.
221
Pythagorean theorem
Relationship between the three sides ofa right triangle: the square of the hypotenuse is equal to the sum of the squares of the other two sides.
222
Quantum
A discrete bundle of energy such as the photon.
223
Quartiles
Values that separate data in ascending order into four evenly sized groups.
224
Radiation
A method of heat transfer that relies on electromagnetic waves; can occur in a vacuum.
225
Radioactive decay
A naturally occurring spontaneous decay of certain nuclei accompanied by the emission of specific particles.
226
Radio waves
Very long wavelength electromagnetic radiation.
227
Radom error
In an experiment, error caused by natural variation in subjects and data points that can be reduced in impact by increasing sample size.
228
Randomization
A method of reducing bias and confounding during research in which participants are assigned to a group by a random number generator or similar method; participants or researchers cannot choose the groups.
229
Range
The difference between the smallest number in a data set and the largest.
230
Ray diagram
Visual representation of a geometrical optics system.
231
Real
Describes an image on the same side of a lens or mirror as the refracted or reflected light that can be projected on a screen; in single-mirror or single-lens systems, real images are always inverted.
232
Reacticular propagation
A phenomenon in which light travels in a straight line when passing through a homogeneous medium.
233
Reflection
The return of light rays from a medium at an angle equal to the incident angle.
234
Refraction
The bending of light rays as a result of a change in the index of refraction between media.
235
Resistance
A measure of the opposition to current flow through a material, measured in ohms (omega); the inverse of conductance.
236
Resistivity
A measure of the intrinsic resistance of a material independent of its shape or size; resistivity generally increases with temperature.
237
Resonance
Oscillation at maximum amplitude as the result of a periodically applied force at the natural (resonant) frequency of an object.
238
Respect for persons
A principle of research ethics that encompasses autonomy and informed consent.
239
Resultant
The sum, difference, or product of vector mathematics; also refers to the sum or difference of two waves.
240
Right-hand rule
A method for determining the direction of a vector that is the product of two vectors.
241
Rotation
The turning of an extended body about an axis or center.
242
Sample
A subset of a population that is used to make generalizations about the population as a whole.
243
Scalar
A mathematical quantity that lacks directionality.
244
Scientific method
A systematized way of evaluating data and investigating new hypotheses.
245
Scientific notation
A mathematical representation of quantities as multiples of powers of ten.
246
Selection bias
Occurs when research participants differ from the general population in a meaningful way.
247
Series
An arrangement of circuit elements in which the current must go through all of the elements.
248
Shear forces
Also called tangential forces, forces exerted on the surface ofan object that are parallel to the surface of the object.
249
Shock waves
The buildup of wave fronts that occurs when the source is traveling at or above the speed of sound.
250
SIgnificant figues
A tool for maintaining appropriate levels of precision when performing mathematical calculations.
251
Simple machine
A basic mechanical device for applying a force. The six simple machines include inclined planes, wedges, wheel and axle systems, levers, pulleys, and screws.
252
Single-blind experiment
An experiment in which only the subject or the assessor is blinded, but the other party is aware of the treatment the subject is
receiving.
253
SI units
The International System
254
Snell's law
Relates the incident angle, refracted angle, and indices of refraction for two media.
255
Solid
A material with distinct bound- aries and strong intermolecular forces capable of resisting shear forces.
256
Sound
The perception of longitudinal waves of pressure changes in air and other media.
257
Source charge (Q)
ln electrostatics, the charge which creates the electric field.
258
Specific gravity
The ratio of an object's density to the density of water; unitless.
259
Specific heat
The relationship be- tween thermal energy and temperature change per unit mass of a substance, measured in J/ g*K.
260
Speed
The ratio of distance travleed to time; at any given point, instantaneous speed is the magnitude of instantaneous velocity; measured in m/s.
261
Spherical abberation
A blurring of the the periphery of an image as a result of inadequate reflection of parallel beams at the edge of a mirror or lens.
262
Sperical mirror
A mirror that causes convergence or divergence of light rays incident upon its surface.
263
Standard deviation
A measure of distribution of data from the mean of a sample; outliers lie at least three standard deviations above or below the mean.
264
Standing waves
Waveforms with steady nodes and antinodes formed from the interference of incident and reflected waves at a boundary.
265
State functions
Physical quantities that can be determined based on the state of an object, such as pressure, density, temperature, volume, enthalp) internal energy, Gibbs free energy, and entropy; pathway independent.
266
Static friction
The friction that existi between a stationary object and the surface upon which it rests.
267
Statistic
A measure of sample data.
268
Streamlines
Visual representation of the movement of fluid during lamina flow.
269
Strong nuclear force
One of the four fundamental interactions; it is responsible for the binding of protonss and neutrons together in the nucleus.
270
Surface tension
The result of the cohesve forces in a liquid creating a barrier at the interface between a liquid and the environment.
271
Surroundings
Everything that is not being measured as part of a given system.
272
System
The obsrved and quantified region of the region of interest to the experimenter. Systems can be isolated (unable to exchange energy or matter with their surroundings), closed (able to exchange energy with their surroundings), or open (able to exchange matter and energy with their surroundings).
273
Systematic error
An error in an experiment that is typically caused by measuring instruments and creates a flaw in data that cannot be offset by increasing data pool.
274
Temperature
A measure of the average kinetic energy of particles in a substance; measured in degrees Fahrenheit {°F), degrees Celsius (0 C), or kelvins (K).
275
Temporality
A necessary criterion for causality; the independent variable must occur before the dependent variable.
276
Terminal velocity
The velocity at which air resistance is equal
| to gravitational force and no acceleration occurs for an object in free fall.
277
Test charge (q)
In electrostatics, the charge placed in an electric field.
278
Thermal equilibrium
Equilibrium of thermal energy that exists when no heat flows between two objects in thermal contact.
279
Thermal expansion
An increase in length or volume of a substance as a result of an increase in temperature.
280
Threshold frequency
The minimum frequency of light that causes ejection of electrons.
281
Timbre
The quality of sound produced by an instrument.
282
Torque
The primary motivator for rotational movement that combines force, lever arm, and the angle between them; measured in N-m.
283
Total internal reflection
A phenomenon in which all the light incident on a boundary is reflected back into the original material.
284
Total mechanical energy
The sum of an object's potential and kinetic energies.
285
Translation
Motion through space without rotation.
286
Transverse wave
A wave that propagates in a direction perpendicular to the direction of oscillation.
287
Traveling wave
A wave that propagates through a medium with changes in the locations of crests and troughs.
288
Turbulent flow
Fluid movement that does not follow parallel streamlines; has backflow, eddies, and swirls.
289
Twin study
A research design used heavily in psychology to differentiate between genetic and environmental effects.
290
Type 1 error
An error in conclusion in which the null hypothesis is incorrectly rejected.
291
Type 2 error
An error in conclusion in which the experimenter fails to correctly reject the null hypothesis.
292
Ultrasonic
Above the frequencies that humans can bear.
293
Ultrasound
A treatment and diagnostic modality using ultrasonic waves for medical purposes.
294
Ultraviolet
A region of the electromagnetic spectrum that is not visible; primarily responsible for the damaging effects of sunlight on skin.
295
Unnatural process
In thermodynamics, a process which does not undergo naturally preclicted changes in heat/ energy over time.
296
Upright
Describes an image that is the same orientation as the object; in single-mirror or single-lens systems, upright images are always virtual.
297
Vaporization
The phase transition from liquid to gas; also called boiling or evaporation.
298
Vector
A mathematical quantity that has both magnitude and direction.
299
Ventuir effect
Describes the relationship between the continuity equation and Bernoulli's equation; as cross-sectional area of a tube decreases, the speed of the fluid increases, and
the pressure exerted on the walls of the tube decreases.
300
Virtual
Describes an image on the opposite side of a lens or mirror as the refracted or reflected light; in single-mirror or single-lens systems. virtual images are always upright.
301
Viscosity
A measure of the resistance to flow in a fluid.
302
Viscous drag
A nonconservative force exerted by fluids in a manner proportional to the viscosity of the fluid.
303
Visible region
The part of the electromagnetic spectrum visible to the human eye.
304
Voltmeter
A device used to measure voltage.
305
Wavelength
The distance between two corresponding points ofsuccessive cycles in a waveform, measured in meters.
306
Weak nuclear force
One of the four fundamental interactions; it is responsible for radioactive decay and contributes to nuclear stability.
307
Weight
The force of gravity acting on an object.
308
Work
A function of the applied force and the distance through which it is applied or the pressure and volume changes in a gas system; work is the use of energy to accomplish something and is measured in joules (J).
309
Work-energy theorem
States that net work is equal to the change in energy (usually kinetic energy) of an object.
310
X-rays
A type of electromagnetic radiation; primarily used for medical imaging.
311
Zeroth law of thermodynamics
If two thermodynamic systems are in thermal equilibrium with a third system, they are in thermal equilibrium with each other
312
Convex
A surface that has a similar curvature to the exterior of a sphere.
