vocab list

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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 10 b ) Scientific Theory – a model based on numerous observations, supported by experimental results that may explain how things work

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Page 1: Vocab List

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

Page 2: Vocab List

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

Page 3: Vocab List

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

Page 4: Vocab List

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

Page 5: Vocab List

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

Page 6: Vocab List

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

Page 7: Vocab List

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

Page 8: Vocab List

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

Page 9: Vocab List

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

Page 10: Vocab List

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

Page 11: Vocab List

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

Page 12: Vocab List

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

Page 13: Vocab List

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