acceleration
the rate of change of velocity; change in velocity over change in time
amplitude
the distance from the equilibrium position of a transverse wave to the top of a crest or the bottom of a trough
analysis
the process of organizing and making sense out of the results of the experiment and comparing this to the original hypothesis; can lead to a modification of the hypothesis
angle of incidence
an angle between an incoming light ray and the normal line
angle of reflection
an angle between the normal line and a reflected light ray
applied force
an external force acting on an object; usually from a person; diagram label is FA
average velocity
total displacement ÷ time interval
carrier particle
a sub atomic particle that transfers force from one object to another
CAT scan
computerized tomography scan, which is a very precise X-ray that looks at specific sections of the body
centripetal acceleration
acceleration of an object moving at a constant speed in circular motion; this acceleration always points to the center of the circle
charge
a basic property of matter
All matter can be positive, negative or neutral based on the number of electrons and protons that it contains. The variable for charge is q.
circuit
a closed conducting loop that use the flow of charge to perform a specific task
closed system
a system in which the mass doesn’t change
comparative investigation
an investigation where observations are made that compare two objects or phenomena
conclusion
a statement that adequately explains or solves the original problem based on the results of scientific experimentation
conduction
transfer of heat energy from molecule to molecule by direct contact of particles
conductor
material that allows charge to move easily
contact force
a force that requires physical contact
Examples include: your fingers pushing the keys on the computer, a baseball bat hitting a ball.
convection
heat transfer in a liquid or gas by movement of particles from one area to another
convex lens
a lens that is thicker in the middle than it is on the edges, if viewed from the side; also called converging lenses
coulomb
the unit of charge; the abbreviation for the coulomb is C
1C of charge represents 6.24 * 1018 protons (or electrons.)
circular motion
motion in a circular path
crest
the highest point of a transverse wave above the equilibrium position
current
the rate at which electric charge moves through a particular point of an electric circuit; the unit is the ampere (A)
Delta, Δ
a numeric operator, which is shorthand for 'final – initial'
Delta must have a variable to operate on. You will not solve any equation for Delta.
dependent variable
a characteristic of an experiment that is a result of the effect or influence of an independent variable
descriptive investigation
an investigation where observations of new phenomena are recorded and catalogued
diffuse reflection
reflection off of a rough surface where parallel light rays are scattered in all directions
direction
the direction an object is moving, in vectors it is shown by the direction of the arrow
displacement
an object's change in position (final position – initial position)
durable
long lasting, capable of withstanding scrutiny
elastic potential energy
energy stored in a spring or energy stored by compressing or stretching an object
electric field
the effect a charge has on the space around it
electric potential
the electrical potential energy of a charged particle divided by the charge of the particle
emission spectrum
series of bright lines or bands of light given off by an excited atom
Spectra are like fingerprints, they are different for each atom.
energy
the capacity to do work
empirical data
data collected from reliable measurement or observation
equilibrium
an object is at equilibrium when it's acceleration is zero; it is at rest or moving at constant velocity
evidence
objective findings during a scientific investigation that either support or do not support the hypothesis
excited state
state of higher energy in an atom
experimental investigation
an organized scientific investigation that is designed to test the hypothesis; includes independent and dependent variables and only attempts to test one variable at a time
explanation
statement that helps make something comprehensible (understandable)
falsifiable
capable of being shown to be false if it is untrue
field
the effect a charge or mass has on the space around it
field force
a force that can act at a distance; a force that can interact without being in contact
Examples include: gravity and attraction or repulsion between magnets.
final position (df)
the location of an object at the end of a time interval
focal length
the distance from a convex lens to its focus, or focal point
focus
the place at the focal length of a convex lens where light rays parallel to the axis of the lens are brought to a point
force
changes motion of an object
Push or pull that can cause an object to accelerate. (SI unit is the Newton.)
force diagram
a diagram that uses arrows to depict the vectors of forces acting on objects in the diagram
frame of reference
a coordinate system used to determine the exact location of an object in space
free body diagram
a force diagram that show all the force vectors acting on an object; it does NOT depict reaction forces
friction
a force that resists motion between two objects in contact; diagram label is Ff or f
generator
a machine that converts mechanical energy to electrical energy
gravitational potential energy
energy stored due to the height an object is above the ground
ground state
lowest energy state of an atom
heat
energy that is transferred between objects due to a difference in temperatures
heat transfer
transfer of heat (energy) from one object to another
highly reliable
something that has been researched frequently that displays little or no change after repeated experiments
horsepower or hp
another unit of power, 1 horsepower = 746 watts (SI unit is the watt)
hypothesis
a proposed explanation, based on observation and research, to a scientific question
impulse
Change in momentum J = Δp = FΔt
independent variable
a characteristic of an experiment that determines the value of the other (dependent) variable(s)
initial position (di)
the location of an object at the beginning of the time interval
instantaneous velocity
the velocity of an object at some specific point along its path (its velocity at some instant in time)
insulator
material that does not allow charge to move
intensity
property describing the brightness of light; dependent on the number of photons present in the light
investigation
method of gathering data by observation, testing a hypothesis, or comparing in order to solve a problem or answer a question
isotope
form of element with same atomic number; each of two or more forms of a chemical element with the same number of protons but with different numbers of neutrons
iterative process
any process that can result in the repetition of previous steps after revisions based on observations of collected data
joule
the SI unit of energy; the product of the force and the displacement of an object; units are N.m
kinetic energy
energy of an object due to its motion; related to the mass and velocity of the object; its unit is the joule
laser
a specialized light source that emits a very powerful narrow beam of light that is all the same wavelength
Laser stands for Light Amplification through Stimulated Emission of Radiation.
Law of Reflection
angle of incidence equals the angle of reflection: θi = θr
lens
a transparent object that refracts light rays, and makes them converge or diverge to form an image
magnetic domain
microscopic groups of atoms within magnetic materials in which the magnetic fields of the atoms are in the same direction
magnetic field
the region surrounding a magnet in which a second magnet, a moving charge, or current-carrying wire will experience a magnetic force; represented by the symbol B and measured in Tesla (T) units
magnetic pole
a region on a magnet which produces a magnetic force; all magnets have a north magnetic pole and a south magnetic pole
magnitude
the size of something, in this particular case, the size of a vector
mechanical energy
energy that an object or group of objects has due to its position or motion
model
a replica, representation, or description designed to show how an object, system, or idea is constructed or how it works
motor
a device that converts electrical energy into mechanical energy
momentum
a quantification on the motion of an object
motion
the change in position or location of an object in relation to time
MRI
magnetic resonance imaging: the use of nuclear magnetic resonance of atomic nuclei to produce high-resolution images
natural phenomena
any observable occurrence of the natural world
net force
the vector sum of all forces acting on an object
net work
the total work done; this can be either adding up the work from each force or finding the work done by the net force
non-supported
not confirmed, sustained or maintained
normal force
force from a surface that reacts to forces pushing into the surface
Example: the floor supporting your weight. Diagram label is N.
normal line
reference line drawn perpendicular to a mirror which is used for measuring angles of incidence and reflection
observation
a method of data collection that includes collecting quantitative and qualitative data
ohm
the unit for resistance (Ω)
Ohm's Law
electrical resistance is constant over a wide range of applied electrical potential differences
one-dimensional motion
motion of an object that occurs in only one direction
parabola
a symmetrical open plane curve formed by the intersection of a cone with a plane parallel to its side
parallel
a circuit with more than one path for charge to flow
photoelectric effect
the emission of electrons from a metallic surface when light of a specific energy shines on the metal
photoelectron
the electrons that are emitted from the surface of a metal when light shines on the metal
photon
a quantum of electromagnetic (light) energy
plane mirror
a mirror with a flat surface
potential difference
the change in the electrical potential energy of a charged particle divided by the charge of the particle; often called voltage; the unit is the volt (V)
potential energy
energy of an object due to its position relative to another object; energy stored within an object
At the atomic level, it is associated with the electric forces that exist between the charged particles of an atom or molecule.
power
the rate at which work is done or energy is transferred
pressure
force per unit of area
projectile motion
motion of an object flying through the air with no forces but gravity
quantify
assigning a numerical value to something
question
a problem that cannot be answered by simple observation or by research
measuring instrument in which the echo of a pulse of microwaves and radio waves is used to detect and locate distant objects
heat transfer by electromagnetic radiation; can go through a medium or no medium
astronomical telescope that picks up electromagnetic radiations in the radio-frequency range from extraterrestrial sources
ray diagram
a diagram using selected rays passing through a convex lens to predict images formed by the lens
real image
an image formed by rays of light that intersect and can be projected onto a screen; light rays actually pass through this point
reflection
the 'bouncing back' of light waves at the surface of an object
refracts
light bends when it passes from one medium to another
repeat-testing
experimental processes using repetition to confirm previous experimental findings
resistance
opposition to the flow of charge through a conductor; the unit is the ohm (Ω)
resistivity
a measure of how much a material resists the flow of charge
resultant vector
sum of two or more vectors; can be said to be one vector that replaces two or more
Rube Goldberg machine
a complex system of interactions put together to accomplish a simple task
scalar
having only magnitude, not direction
scientific investigation
a structured way for investigating phenomena, acquiring new knowledge, or correcting and integrating previous knowledge
scientific methodology
an organized system used by scientists to perform investigations that help to develop an accurate explanation of observations
series
a circuit with only one path for charge to flow
sigma, Σ
the Greek letter sigma → the sum of
sonar
a measuring instrument that sends out an acoustic pulse in water and measures distances in terms of the time for the echo of the pulse to return; an acronym for "sound navigation and ranging"
specific heat
the amount of energy required to raise the temperature of 1 kilogram of a substance 1° Celsius at constant pressure
specular reflection
reflection off of a smooth surface where parallel light rays will all reflect in the same direction according to the law of reflection θi = θr
standard nomenclature
a standard set of variable names and vocabulary used in a science
supported
confirmed, sustained or maintained
technology
application of knowledge to solve problems or create new tools
temperature
the measure of the average kinetic energy of the particles in a substance
tension
a force applied along a rope or stretched spring; diagram label is T
testable
something that can be investigated using a controlled experiment
thermal energy
the total of all the energy contained in a substance due to the random motion of its individual atoms or molecules
time
how long it takes something to happen; the duration of a problem in seconds
transformer
two coils of wire used to increase or decrease voltage
trough
the highest point of a transverse wave above the equilibrium position
two-dimensional motion
motion that is occurring in two different directions at the same time
ultrasound (ultrasonography)
using the reflections of high-frequency sound waves to construct an image (a sonogram); commonly used to observe fetal growth or study bodily organs
variable
something that may be changed or manipulated during an investigation
vector
a quantity that has both magnitude (size) and direction
velocity
the rate of change of the position of an object in a certain direction
virtual image
an image formed by light rays that only appear to intersect and cannot be projected onto a screen
watt
SI unit of power; defined as a joule/second
wavelength, λ
the distance from the top of a crest to the top of the next crest, or from the bottom of a trough to the bottom of the next trough
weight
the force of gravity on an object; diagram label is W or mg
well-established
having been in accepted existence for a long time; standing up to scrutiny
work
the product of the magnitude of force exerted on an object in the direction of motion and the actual displacement of the object
work-kinetic energy theorem
states that the net work done on an object is equal to the change of the kinetic energy of that object
X ray
electromagnetic radiation of short wavelength produced when high-speed electrons strike a solid target