Regents Review

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Regents Review
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Mechanics Mass and WeightWhat you need to know

• Mass and inertia are the same thing.
• Mass and inertia are not a force.
• Constant velocity or zero velocity means that the
  net force (Fnet) is zero.
• Weight is mg and is measured in Newtons.
• Mass is the same everywhere while weight will
  change depending on the strength of gravitational
  attraction.

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Mechanics Linear Motion

• Constant velocity and zero velocity mean that the
  acceleration is zero.
• Displacement, velocity and acceleration are
  vectors.
• The slope of a distance vs. time graph is the
  velocity.
• The slope of a velocity vs. time graph is the
  acceleration.
• The area under a velocity vs. time curve is the
  displacement.

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Vectors

• Magnitude equals the size of a vector quantity.
• At zero degrees
• Two vectors have a resultant equal to the sum of
  their individual magnitudes.
• At 180
• Two vectors combine to equal their difference.
• The equilibrant is a vector whose magnitude is
  equal and opposite the resultant vector

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Vector vs. Scalar

• Vectors
• Displacement (d)
• Velocity (v)
• Weight / Force (F)
• Acceleration (a)
• Electric Field Int. (E)
• Magnetic Field Int. (B)

• Scalars
• Distance (d)
• Speed (v)
• Mass (m)
• Time (t)
• Work Energy (J)
• Voltage (V)
• Power (W)

Note Vectors are normally represented in bold
face while scalars are not.
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Mechanics - Forces

• A force is a push or pull on an object.
• Forces can exist as long-range forces
  (electrostatic, magnetic or gravity), or as
  contact force (touching).
• All the forces acting on a system can be added up
  to determine the net force (Fnet).
• Friction is a force that opposes motion between
  two bodies.
• Use free-body diagrams and coordinate axes to
  help analyze problems with forces.
• Analyze forces in the x-direction separate from
  those in the y-direction.

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Mechanics Newtons 1st Law of Motion

• An object in motion will remain in motion in a
  straight line at constant speed, or an object at
  rest will remain at rest unless acted upon by an
  unbalanced force.
• 1st Law is also known as the Law of Inertia.
• Inertia ? mass.
• Inertia is an objects resistance to change in
  motion.

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Mechanics Newtons 2nd Law of Motion

• The acceleration of an object is directly
  proportional to the force applied to it and
  inversely proportional to its mass.
• As force increases (mass constant), acceleration
  increases.
• As mass increases (force constant), acceleration
  decreases.
• a Fnet/m
• Fnet sum of external forces acting on an object.

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Mechanics Newtons 3rd Law of Motion

• An interaction pair exists as two forces that are
  equal in magnitude and opposite in direction.
• Law of action-reaction For every action,
  there is an equal and opposite reaction.
• The interaction pair of forces act on two
  different objects e.g. Fg(ball on earth)
  -Fg(earth on ball).
• Because the forces act on two different objects,
  they do not necessarily cancel out.

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Waves What you need to know.

• A wave is a traveling disturbance that carries
  energy through space and matter without
  transferring mass.
• Transverse Wave A wave in which the disturbance
  occurs perpendicular to the direction of travel
  (Light).
• Longitudinal Wave A wave in which the
  disturbance occurs parallel to the line of travel
  of the wave (Sound).
• Surface Wave A wave that has charact-eristics of
  both transverse and longitudinal waves (Ocean
  Waves).
• Mechanical Waves Require a physical medium such
  as air, water or steel (Sound).
• Electromagnetic Waves Do not need a physical
  medium (X-rays, Light, Radio Waves ).

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Wave Characteristics What you need to know.

• Crest The high point of a wave.
• Trough The low point of a wave.
• Amplitude Maximum displacement from its position
  of equilibrium (undisturbed position).
• Measure of the energy of a wave.

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Wave Characteristics What you need to know.

• Frequency(f) The number of oscillations the wave
  makes in one second (Hertz 1/seconds).
• Wavelength(?) The minimum distance at which the
  wave repeats the same pattern ( 1 cycle).
  Measured in meters.
• Velocity (v) v f? - speed of the wave (m/s).
• Period (T) Time it takes for the wave to
  complete one cycle (seconds).

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Wave Interference What you need to know.

• Interference occurs whenever two waves occupy the
  same space at the same time.
• Law of Linear Superposition When two or more
  waves are present at the same time at the same
  place, the resultant disturbance is equal to the
  sum of the disturbances from the individual
  waves.
• Constructive Interference When two or more waves
  combine to form a larger resulting disturbance.
• Destructive Interference When two or more waves
  combine to form a smaller resulting disturbance.
• Phase A measure of synchronicity of two or more
  waves.
• In Phase Constructive Interference
• Out of Phase Destructive Interference

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Reflection, Refraction, Diffraction, Dispersion
What you need to know.

• Law of Reflection The angle of incidence is
  equal to the angle of reflection as measured
  from the normal (perpendicular to the surface).
• Refraction Phenomena where a wave bends towards
  the normal when going from a less dense medium to
  a more dense medium.
• Diffraction Phenomena where a wave spreads out
  after passing through a narrow opening. The
  smaller the opening the greater the diffraction.
• Dispersion A prism will break white light up
  into its individual wavelengths (Shortest ? bends
  and slows down the most).

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Doppler Effect What you need to know.

• Doppler Effect
• When the distance between a wave source and an
  observer decreases, the detected wave will have a
  shorter wavelength and higher frequency (The
  converse is true if they are moving apart.)

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Light What you need to know.

• Electromagnetic Spectrum Light is a form of
  electromagnetic radiation containing radio waves,
  infrared, visible, ultraviolet, x-ray and gamma
  rays.
• Shorter wavelengths of light have more energy
  (gamma, x-ray, blue).
• Shorter wavelengths of light are bent more when
  entering a substance with a higher index of
  refraction (n).
• At the critical angle, all light will be
  refracted at 90. Beyond the critical angle, all
  light will be internally reflected (fiber optic
  cable).
• Light waves are transverse waves, and therefore
  can be polarized.
• All light travels at 3.0 x 108 m/s in a vacuum.

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Light What you need to know.

• The wave nature of light is proven through
  diffraction, interference and polarization.
• Monochromatic light is comprise of only one
  frequency.
• Coherent light is comprised of light where all
  the waves are in phase (lasers).

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Static Electricity What you need to know.

• Electrons and protons have equal and opposite
  charges (1.6 x 10-19C).
• Robert Millikan determined the charge of an
  electron with the oil drop experiment.
• Like charges repel.
• Dissimilar charges attract.
• Charge is conserved
• If two charged bodies come in contact with each
  other, add the two charges together and then
  divide by two to find the final charge on each
  body.
• Changes in charge result from the movement of
  electrons, not protons.
• The force between two like or dissimilarly
  charged bodies can be determined using Coulomb
  Law
• F kq1q2
• r2

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Electric Fields What you need to know.

• The electric field strength or intensity A
  measure of the amount of force Fe exerted on a
  test charge q.
• E Fe/q
• Electric field lines point away from positively
  charged objects and towards negatively charged
  objects.
• Electric field lines begin and terminate on the
  surface of charged metallic bodies.
• Electric field lines are perpendicular to the
  surface.

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Electric Potential What you need to know.

• Electric Potential Difference The work required
  to move a test charge through an electric field
  divided by the magnitude of the test charge.
• V W/q
• Electric field lines intersect lines of
  equipotential at right angles.
• The potential is a constant at a given distance
  from a charged object where E is constant as
  well e.g. two parallel plates.
• V Ed

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Current Electricity What you need to know.

• Insulators Materials in which electrons do not
  flow freely.
• Conductors Materials in which electrons flow
  easily.
• Ionized gasses conduct electricity e.g. air and
  lightening.
• Resistance The hindrance to the flow of charge.
• Short fat cold wires make the best conductors
• (R ?L/A).
• Low R Low L
• Low R Large x-sectional area
• Ohms Law
• A linear relationship where R V/I

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Series Circuits What you need to know.

• Sum of voltage drops around a circuit equals the
  voltage source.
• Requivalent R1 R2 R3
• Total resistance will increase if a resistor is
  added.
• Current is the same for each resistive element in
  the circuit.

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Parallel Circuits What you need to know.

• Total current into a node (intersection between 3
  or more wires) 0.
• 1/Requivalent 1/R1 1/R2 1/R3
• Total resistance will decrease if a resistor is
  added.
• Voltage is the same for each resistive element in
  the circuit.

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Magnetism What you need to know.

• The direction of the magnetic field is the same
  as the direction that the compass needle points.
• Magnetic field lines point from North to South
  outside the magnet and from South to North inside
  the magnet.
• Magnetic fields are strongest at
• the poles.
• Temporary magnets exist only in
• the presence of an external
• magnetic field.

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Electromagnetism What you need to know.

• Current flowing in a wire produces a magnetic
  field, as does any charge in motion.
• Two wires parallel to each other
• Current flowing in the same direction
  attraction.
• Current flowing in opposite directions
  repulsion.
• Use RHRs to determine the direction of the
  magnetic field and forces with respect to the
  movement of positive charges.
• The magnetic field of a coil will increase when
• iron is added to the core.
• the number of windings is increased.
• the current going trough the coil is increased.

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Electromagnetic Induction What you need to know.

• Electromagnetic Induction When a conductor is
  moved perpendicular to a magnetic field, or a
  magnetic field is moved perpendicular to a
  conductor, a current will be induced in the
  conductor.
• Lenzs Law
• An induced current in a coil produces a magnetic
  field that opposes the external changing magnetic
  field.
• If the magnetic field is not changing, no current
  will be induced.
• A motor converts electrical energy into
  mechanical energy
• A generator converts mechanical energy into
  electrical energy.

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Work Power (Electricity) What you need to
know.

• Whenever a charge moves because of an electric
  force, whether caused by an electric field or
  another charge, work is done on that charge.
• W qEd (may be referred to as PEelectric)
• W qEd qV
• Power is the amount of work done per unit of
  time, or the rate of conversion of electrical
  energy into other forms of energy (light,
  mechanical energy, thermal energy, etc).
• P W/?t q?V/?t
• P VI
• P V2/R
• P I2R

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Modern Physics What you need to know.

• Wave Particle duality of light Light has
  attributes of both waves and particles.
• Wave Nature Diffraction, interference and
  polarization.
• Particle Nature Light comes in discrete packets
  called photons.
• Matter Waves All particles moving in nature do
  so as waves with a very high frequency and short
  wavelength (deBroglie)

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Spectral Emissions What you need to know.

• The lowest energy state of an atom is called the
  ground state.
• An atom not in the ground state, but still with
  all of its electrons is said to be excited.
• An atom that loses an electron is ionized.
• The EM energy required to transition an electron
  from the ground state to an excited state occurs
  in discrete quantities of energy (Ephoton hf
  hc/? Ei - Ef)
• A photon of energy equal to the difference in
  energy levels will be emitted when an electron
  transitions from a higher energy level to a lower
  energy level.

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Matter Energy What you need to know.

• E mc2
• Energy can be converted from one form to another.
• Matter can be converted into energy in the form
  of heat or light

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Standard Model What you need to know.

• All matter is comprised of leptons and hadrons.
• Leptons Elementary particles of which the
  electron is the best known.
• Hadrons consist of baryons and mesons.
• Baryons Are comprised of three quarks
• Proton up, up, down (uud)
• Neutron up, down, down (udd)
• Mesons Are comprised of one quark and one
  antiquark.
• For every particle, there is an anti-particle
  with a charge that is equal and opposite.

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Standard Model Fundamental Forces - What you
need to know.

• Strong Force The strongest of the 4 forces
• Is only effective at distances less than 10-15
  meters (about the size of the nucleus)
• Holds quarks together
• This force is carried by gluons
• Weak Force
• 10-13 times weaker than the strong force.
• Involved in beta decay.
• This force is carried by the W and Z bosons.

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Standard Model Fundamental Forces - What you
need to know.

• Electrostatic Force
• Causes opposite charges to attract and like
  charges to repel
• Carried by a particle called a photon
• Its effects decrease with the inverse square of
  the separation
• Gravitational Force Weakest Force
• Has a negligible effect on elementary particles
• A long-range force
• Carried by the graviton

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Electrostatics
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Current Electricity
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Magnetism
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Waves
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Light Optics
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Mechanics
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Constants
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F

• Stands for?
• Force
• The Units are?
• Newtons (N)

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r

• Stands for?
• Radial distance between two points or objects.
• The Units are?
• meters (m)

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E

• Stands for?
• Electric Field Intensity or Strength.
• The Units are?
• N/C (F/q)
• V/m (V/d)

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q

• Stands for?
• Charge
• Units are?
• Coulombs (C)
• Alternate symbol representation
• Q or e

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I

• Stands for?
• Current (Flow of positive charge).
• Units are?
• Amperes (A)

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V

• Stands for?
• Volts / Voltage / Potential Difference / Electric
  Potential
• The Units are?
• Volts

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R

• Stands for?
• Resistance (An electrical property of a material
  that is a measure of the resistance to flow of
  electrons in relation to an electrical
  potential.)
• The Units are?
• Ohms (?)

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?

• Stands for?
• Resistivity (A natural property of a material
  that is a measure of the resistance to the flow
  of electrons.)
• The Units are?
• ?m

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A

• Stands for?
• Cross-sectional area (of a conductor).
• The Units are?
• m2

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L

• Stands for?
• Length (of a conductor).
• The Units are?
• m

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E

• Stands for?
• Energy
• The Units are?
• Joules (J)

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W

• Stands for?
• Work
• Often used interchangeably with kinetic energy
  (KE ½mv2).
• The Units are?
• Joules (J)

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P

• Stands for?
• Power
• The Units are?
• Watts (W)
• Joule per second (J/s)

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B

• Stands for?
• Magnetic Field Intensity.
• The Units are?
• Tesla (T)

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c

• Stands for?
• Speed of light
• The Units are?
• m/s
• The Value is?
• 3.0 x 108 m/s

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f

• Stands for?
• Frequency (The number of waves that pass a point
  in space per unit of time.)
• The Units are?
• Hertz (Hz), cycles/second, or (1/s)

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T

• Stands for?
• Period (The time required for a wave to complete
  1 cycle, or one wavelength.)
• The Units are?
• Seconds (s)

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?

• Stands for?
• Wavelength (The distance at which a wave will
  repeat the same pattern over again.)
• The Units are?
• Meters (m)

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v

• Stands for?
• Velocity (Sometimes interchangeably used with
  speed.)
• The Units are?
• meters per second (m/s)

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n

• Stands for?
• Index of refraction (property of a material that
  is used to determine both the speed of light in
  that material and the amount that the light will
  bend.)
• Quantum energy level.
• The Units are?
• None

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?i, ?r, ?1, ?2

• Stands for?
• Angle of incidence (?i)
• Angle of reflection (?r)
• Angle of incidence (?1)
• Angle of refraction (?2)
• All angles are relative to a normal to the
  surface.

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h

• Stands for?
• Planck's Constant
• The Units are?
• Joule second (J.s)
• The value is
• 6.626 x 10-34 J.s

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k

• Stands for?
• Electrostatic constant
• The Units are?
• Newtons meters2 / Coulombs2 (Nm2/C2)
• The Value is
• 8.99 x 109 Nm2/C2

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e

• Stands for?
• Elementary charge
• Charge on a proton or electron
• The Units are?
• Coulombs (C)
• The Value is
• 1.6 x 10-19 C