vocab list
TRANSCRIPT
Unit 1: Introduction
Accuracy – how well the results of a measurement agree with the “accepted” value
Dependent Variable – the factor in an experiment that depends on the independent variable
Derived Unit – a combination of fundamental units used to simplify notation
Dimensional Analysis – a method of treating units as algebraic quantities
Direct Relationship – a linear relationship that passes through the origin
Hypothesis – a testable, educated guess
Independent Variable – the factor that is manipulated during an experiment
Inverse Relationship – the product of the two variables is a constant
Line (curve) of Best Fit - a line (curve) that best passes through or near graphed data
Linear Relationship – a relationship between two variables whose graphed data points lie on a straight line
Measurement – a comparison between an unknown quantity and a standard
Physics – the study of matter and energy
Precision – the degree of exactness of a measurement
Quadratic Relationship – a parabolic relationship, one variable depends on the square of another
Scientific Fact – a repeatable observation accepted by experts in the field
Scientific Law – a well established rule that describes, but does not explain a pattern in nature
Scientific Method – a systematic method of observing, experimenting and analyzing to answer questions about the natural world
Scientific Notation – a standard method of writing numbers ( a x 10b)
Scientific Theory – a model based on numerous observations, supported by experimental results that may explain how things work
Significant Digits – the valid digits in measurement the number of which indicates the precision of a measurement
Unit – a standard quantity with which other similar quantities can be compared
Unit 2: Modeling Motion
Acceleration - the time rate of change of the velocity
Acceleration due to Gravity – the acceleration of an object in free fall (g)
Average Velocity – displacement / time
Displacement – the change in the position of an object
Distance – the total length of a path that an object travels
Free Fall – an object moving under the influence of gravity only
Instantaneous Velocity – the velocity of an object at a particular instant in time
Kinetic Energy – the energy of an object due to its motion
Linear Motion – an object’s motion along a straight line (1-dimension)
Meter – fundamental SI unit of length
Origin – a reference point
Position – the straight line distance and direction from the origin
Scalar – a quantity with magnitude (size) only
Second – fundamental SI unit of time
Speed – the distance and object moves in a unit time
Uniform motion – motion with constant velocity (a=0)
Vector – a quantity with magnitude (size) and direction
Velocity – the time rate of change of the position
Unit 3: Newton’s Laws
Action / Reaction – interaction force pair, same magnitude opposite direction
Contact Force – an interaction (force) between two objects that requires touching
Dynamic Equilibrium - forces are balanced, particle is moving, , ,
Equilibrium – forces are balanced, ,
Field Force – an interaction (force) between two objects that does not require contact
Force – an interaction between two objects, a push or a pull
Free Body Diagram –a physical model that represents the forces acting on a system
Friction – contact force that acts to oppose sliding motion between surfaces
Gravitational force – the attractive force between two objects that is directly proportional to the mass of the objects
Inertia – the resistance of an object to a change in its motion
Inertial Mass – a measure of an object’s inertia
Net force – the vector sum of the forces (resultant)
Newton – the force that imparts a 1 m/s2 acceleration on a 1-kilogram mass, a derived SI unit for force
Newton’s 1 st Law – an objects motion will be unchanged (equilibrium) if and only if the net force on the object is zero
Newton’s 2 nd Law – the acceleration of an object is directly proportional to the net force and inversely proportion to its mass.
Newton’s 3 rd Law – forces come in pairs (action/reaction)
Normal – contact force between surfaces, perpendicular to the contact surface
Resolution of Forces – the process of determining the components of a force
Resultant – the vector sum
Spring Force – a restoring force, opposite the displacement of the end of the spring
Static Equilibrium – forces are balanced, particle is at rest , ,
Tension – the pull exerted by a string, rope or cable
Thrust- a general term for the forces that move objects such as rockets, planes, cars etc
Unbalanced Force – a nonzero net force
Vector Component – the ‘part’ of a vector in a given direction
Weight – a field force due to gravitational attraction between two objects, generally Earth and an object
Unit 4: Applications of Newton’s Laws
Coefficient of Friction – the ratio of the maximal frictional force and the normal force
Equilibrant - a force that places an object in equilibrium
Gravitational Field Strength – the force per unit mass at a given point in a gravitational field
Gravitational Potential Energy – the energy change of an object resulting from lifting the object to a height above Earth’s surface
Hooke’s Law – the force acting on a spring is directly proportional to the amount that the spring is stretched or compressed
Kinetic Friction - friction that acts on moving objects
Projectile - an object shot through the air that after receiving an initial thrust, travels through the air only under the influence of gravity. [2-d free fall]
Range -the horizontal distance traveled by a projectile
Spring Constant – the constant of proportionality between the applied force and the stretch or compression of a spring, depends on the stiffness of the spring
Static Friction – the frictional interaction between two surfaces when there is no motion between the two surfaces
Trajectory – the path of a projectile through space
Unit 5: Impulse and Momentum
Closed system – a system that does not gain or lose mass
Impulse – the area under the force vs. time graph, the product of the average net force on an object and the time interval over which the force acts
Impulse-momentum theorem – the impulse on an object is equal to the change in the objects momentum. This is a cause and effect relationship.
Law of Conservation of Momentum – the momentum of any closed, isolated system does not change.
Momentum – the product of an object’s mass and velocity
Unit 6: Work and Energy
Conservative Force - a force for which work done by it is independent of the path taken
Elastic Collision – a collision in which the kinetic energy is conserved
Elastic Potential Energy – the potential energy stored in an object due to a change in its shape
Electromagnetic energy –the energy associated with electric or magnetic fields
Energy – the ability to do work
Generator – device that converts mechanical energy into electrical energy
Ideal Mechanical System – a closed system in which no friction or other non-conservative force is acting
Inelastic Collision – a collision for which the kinetic energy after the collision is less than the kinetic energy before the collision
Internal Energy – total potential and kinetic energy of the particles that make up and object, but excluding the energy of the system as a whole
Joule – a derived SI unit equal to the work done when a force of one Newton produces a displacement of 1 meter.
Law of Conservation of Energy – in a closed, isolated system, the total energy in constant
Non-conservative Force – a force for which the work done by it depends on the path taken
Mechanical Energy – the sum of the kinetic and potential energies of a system
Motor – device that converts electric energy into mechanical energy as a result of forces on a current-carrying conductor in a magnetic field
Non-ideal Mechanical System - a system in which a non-conservative force such as friction is acting
Nuclear Energy – the energy released in a nuclear reaction (eg: Fission or Fusion)
Photocell – device that converts light, a form of electromagnetic radiation, to electrical energy
Potential Energy – the energy due to the position or condition of an object,
Power- the rate at which work is done
Simple pendulum – a mass (bob) attached to one end of a string or wire that is attached at the other end to a pivot point
Thermal Energy – a measure of the internal motion of an object’s particles, the total kinetic energy of an object’s particles
Total Energy – the total energy of a non-ideal system is the sum of the PE, KE and Internal Energy
Watt – a derived SI unit for power equal to 1 Joule per second
Work – the transfer of energy by mechanical means; is done when a force is exerted on an object in the direction of motion; area under the Force vs. position graph
Work-Energy Theorem – when work is done on an object, a change in kinetic energy occurs
Unit 7: Fundamental Interactions
Centripetal Acceleration – the acceleration toward the center of a curvature of a curved path
Centripetal Force – the net force causing a centripetal acceleration
Coulomb – the SI standard unit of charge
Coulomb’s Law – the force between two charges varies directly with the product of the charges and inversely with the square of the distance between them
Electric Charge – the property of particles that governs the electromagnetic interaction
Electron – a fundamental particle (lepton) that has a charge of -1e or -1.6 x 10-19 Coulombs
Elementary Charge – the smallest quantity of charge observed in nature e = 1.6 x 10-19 Coulombs
Gravitational Mass – the property of particles that governs the gravitational force
Law of Universal Gravitation – the force between two masses varies directly with the product of the masses and inversely with the square of the distance between them
Neutron – a fundamental particle (baryon) that has a charge of 0e
Nucleon – particles found in the nucleus of an atom (protons & neutrons)
Period – the time required for a repetitive motion to repeat one complete cycle of motion
Proton – a fundamental particle (baryon) that has a charge of +1e or 1.6 x 10-19 Coulombs
Strong Nuclear Force – very Strong, short ranged attractive force between nucleons
Uniform Circular Motion – the motion of an object traveling in a circular path with constant speed
Weak Nuclear Force – short ranged, nuclear force responsible for particle decay
Unit 8: Electrical Properties of Matter
Capacitance – the ratio of an object’s stored charge to its electric potential difference
Capacitor – an electric device used to store charge
Charging by conduction – the process of charging a neutral object by touching it with charged objects
Charging by induction – the process of charging an object without touching it
Conductor – a material through which a charge will move freely
Electric field – the field that exists around a charged object
Electric field line – lines that provide a picture of an electric field
Electric potential difference – the change in electric potential energy per unit charge in an electric field
Electric potential energy – potential energy due to the position of a charge in an electric field
Electronvolt – an small unit of energy; the amount of work necessary to move one electron across a potential difference of 1 Volt
Electroscope – a device that is used to detect electric charges
Electrostatics – the study of charges at rest
Equipotential – the electric potential difference of zero between two or more positions in an electric field
Grounding – the process of removing excess charge by touching an object to the Earth
Insulator – a material through which a charge will not move easily
Law of Conservation of Charge – a material through which a charge will not move easily
Neutral – an object that has a net charge of zero
Volt – a derived SI unit for electric potential difference equal to one Joule per Coulomb
Unit 9: Electric Circuits
Ammeter – a device for measuring electric current
Ampere – the fundamental SI unit of electric current; equal to one coulomb per second
Battery – a combination of two or more electrochemical cells; a direct current voltage source
Cell – a device that converts chemical energy to electrical energy
Conductivity – a property of a material that describes the availability of charges that are free to move under the influence of an electric field
Conventional Current – a flow of positive charges that move from higher potential to lower potential
Electric Circuit – a closed loop or pathway that allows electric charges to flow
Electric Current – the rate at which charges pass a given point
Equivalent Resistance – the single resistance that could replace several resistors in a circuit
Kilowatt-hour – an energy unit used by electric companies to measure energy sales; 1 kWh 3.6x106 Joules
Ohm – the derived SI unit of electrical resistance; equivalent to 1 volt per ampere
Ohm’s Law – at a constant temperature the resistance of a conductor is constant
Ohm-meter – the SI unit for resistivity
Parallel Connection – each circuit element is connected in a separate branch
Resistance – the ratio of the applied voltage across a conductor to the corresponding current through the conductor
Resistivity – a property of a material that describes how strongly a material resists the flow of electrons
Resistor – an electrical device designed to have a definite amount of resistance
Series Connection – all circuit elements are connected end to end to proved a single path for current
Superconductor – a material with zero resistance that can conduct electricity without a loss of energy
Switch – a device for making, breaking or changing the connections in an electric circuit
Voltmeter – a device for measuring potential difference
Unit 10: Magnetism
Domain – a very small region that is formed when magnetic fields of the electrons in neighboring atoms are aligned in the same direction
Electromagnetic Induction – the process of generating a potential difference across a conductor due to the relative motion of the conductor and a magnetic field
Magnet – a material in which the spinning electrons of its atoms are aligned in the same direction
Magnetic Field – the area around a magnet or moving charge where a magnetic force exists
Magnetic Field (flux) Lines – imaginary lines that map out a magnetic field
Magnetic Field Strength (flux) – the number of magnetic flux lines per unit area passing through a surface
Magnetic Force – a force between two charges moving relative to each other
Magnetic Pole – a location where the magnetic field has the highest intensity
Unit 11: Wave Model
Amplitude –in any periodic motion, the maximum displacement of an object from equilibrium
Angle of Incidence – the angle between the incident ray and the normal to the surface at the point where the ray meets a boundary
Angle of Reflection – the angle between the reflected ray and the normal to the surface at the point where the ray meets a boundary
Angle of Refraction – the angle between the refracted ray and the normal to the surface at the point where the ray meets a boundary
Antinode – the point of maximum displacement of a medium when two wave pulses meet
Constructive Interference – the effect produced when two in-phase waves pass simultaneously through a medium causing an increase in amplitude
Crest – the high point in a wave
Decibel –The unit of measurement for sound level
Destructive Interference - the effect produced when two out of-phase waves pass simultaneously through a medium causing a decrease in amplitude
Diffraction – the spreading of wave fronts into a region behind a barrier
Diffuse Reflection – the scattering of light off of a rough surface
Doppler Effect – a change in the observed frequency and wavelength due to the relative motion of a wave source and the observer
Electromagnetic Spectrum – the complete range of frequencies and wavelengths if electromagnetic waves
Electromagnetic Wave – periodically changing electric and magnetic fields that travels through a vacuum
Frequency – the number of cycles of a periodic motion that occur per second
Hertz – derived SI unit of frequency; 1 Hertz = 1 cycle per second
Image – the combination of image points in an optical device from which the object seems to originate
Incident Wave (ray) – a ray that originates in a medium and is incident on a boundary with another medium
Index of Refraction – the ratio of the speed of light in a vacuum to the speed of light in a particular medium
Interference – results from the superposition of two or more waves
Law of Reflection – the angle of incidence is equal to the angle of reflection
Longitudinal Wave – a mechanical wave in which the disturbance is in the same direction, parallel to, the direction of propagation
Mechanical Wave – A wave that can not travel through a vacuum
Medium – material through which waves travel
Monochromatic Light – light of a single frequency (color)
Node – a stationary point where two wave pulses meet, having a displacement of zero
Normal – a reference line drawn perpendicular to a surface
Object – a source of light rays that enter an optical device
Period – the time required for an object to complete one cycle of a periodic motion
Periodic Motion – any motion that repeats itself in a regular cycle
Periodic Wave – a series of regularly repeated disturbances in a field or medium
Phase – the position of a point on a wave relative to another point on the same wave
Pitch – the highness or lowness of a sound wave; depends on the frequency
Plane Mirror – a flat smooth surface form which a wave is reflected
Principle of Superposition – the displacement of a medium caused by two or more waves is the vector sum of the displacements of the individual waves
Ray Model of Light – a model that represents light as a ray that travels in a straight path
Reflected Wave (ray) – a wave that rebounded from a boundary
Refracted Wave (ray) – a ray that results from an incident ray crossing a boundary obliquely
Refraction – the change in direction of a wave as it crosses a boundary obliquely
Resonance –the vibration of an object at its natural frequency due to the action of a vibrating source of the same frequency
Simple Harmonic Motion – a motion that occurs when the restoring force on an object is directly proportional to the object’s displacement from equilibrium
Snell’s Law – the product of the index of refraction of a medium and the sine of the angle that the ray makes with the normal is a constant across a boundary
Sound Level – a logarithmic scale used to measure the amplitude of a sound wave
Sound Wave – a longitudinal pressure variation transmitted through matter
Specular (regular) Reflection – a reflection produced by a smooth surface
Standing Wave – a wave that appears to be standing still; produced by two identical waves traveling in opposite directions
Surface Wave – a mechanical wave in which the particles move both parallel and perpendicular to the direction of propagation
Transverse wave – a wave that vibrates perpendicular to the direction of propagation
Trough – the low point of a wave
Vacuum – a region of empty space
Wave – a vibratory disturbance that propagates through medium or field; transfers energy without transferring matter
Wave Front – continuous points on a wave that are in phase with each other
Wave Pulse – a single vibratory disturbance that propagates through a medium or field
Wavelength – the distance along a wave between two successive points in phase
Wave Speed – the rate at which a wave propagates through a medium or field
Unit 12: Modern Topics
Absorption Spectrum – the characteristic set of frequencies absorbed by a gas
Alpha decay – the emission of an alpha particle from the nucleus
Alpha particle – massive positively charged atomic particle; a helium nucleus
Antimatter – material consisting of atoms which are composed of antiprotons, antineutrons and positrons
Antiparticle – a particle having mass, lifetime and spin identical to the associated particle, but with charge of opposite sign and magnetic moment reversed in sign
Antiquark – the antiparticle of a quark
Atom – the smallest particle of an element
Atomic number – the number of protons in an atom’s nucleus
Atomic Spectrum – a specific series of frequencies of electromagnetic radiation produces when electrons in excited atoms return to lower energy states
Baryon – a hadron made up of three quarks
Beta decay - the emission of a beta particle and an antineutrino from the nucleus
Binding energy – the energy equivalent of the mass defect; always negative
Bright-line ( Emission) Spectrum – a series of bright lines that results from the emission of radiation of specific frequencies by a heated gas
Compton Effect – the shift in the energy of scattered photons
DeBroglie Wavelength – the wavelength associated with a moving particle
Energy level – the quantized amount of energy that an atom may have at each level
Energy level diagram – diagram representing the energy levels of a quantized system
Excited state – any energy level of an atom that is higher than its ground state
Force carrier – particle that transmit, or carry forces between matter
Gamma Decay – the emission of a photon from the nucleus
Ground state – state of an atom with the smallest allowable amount energy
Hadron – a particle made up of quarks, interacts through the strong force
Half-life – the time required for half the atoms in a given quantity of a radioactive element to decay
Ionization potential – the energy required to remove an electron from an atom
Lepton- a particle that interacts through the weak, electromagnetic and gravitation forces
Mass defect – the difference between the sum of the masses of the nucleons and the mass of the nucleus
Mass number – the number of nucleons in the nucleus
Meson – a hadron made up of a quark and an anti-quark
Neutrino – a neutral lepton that has energy and momentum, but almost no mass
Nucleon – a proton or neutron within the nucleus of an atom
Photoelectric effect – the emission of electrons by certain metals when they are exposed to electromagnetic radiation
Photon – quanta of electromagnetic radiation, has energy and momentum, but no mass
Positron – an anti-electron
Quantized – condition that restricts a quantity to discrete amounts, or quanta
Quantum – a discrete packet of some quantity
Quantum model – a model for matter and energy using wave properties and quantization
Quark – tiny particles that make up hadrons
Spectral line – a particular frequency of absorbed or emitted energy
Standard model – a model of matter in which all particles can be grouped into three families; quarks, leptons, and force carriers
Stationary state – any particular orbit that can be occupied by an electron in an atom
Universal mass constant – atomic mass unit equal to 1.66x10-27 kg