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The key takeaways are that the document covers classical mechanics, types of forces, motion, energy, optics and properties of light waves.

The main topics covered in the document include classical mechanics, types of forces, equations of motion, energy, circular motion, optics, properties of light waves including reflection, refraction, diffraction and interference.

Snell's law describes how the angle of refraction of a light ray changes when passing from one medium to another. It states that the ratio of the sines of the angles of incidence and refraction is equal to the ratio of the indices of refraction of the two substances.

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Inc WORLD'S#L ACADEMIC QUTLINE


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Quick
Study
ACADEMIC
PHYSICS
WHAT IS PHYSICS ALL ABOUT?
Physics seeks to understand the natural phenomena |Symbol Unit Other physical quantities are derived from these basic units:
Base Quantity
that occur in our universe; a description
phenomenon uses many speci c terms, de nitions and
of a natural Length ,x Meter - m Pre xes denote fractions or multiples of units; many variable
symbols are Greek letters
Mass m, M Kilogram - kg
mathematical equations Math Skills: Many physical concepts are only understood
Temperature Kelvin- K
Solving Problems in Physics with the use of algebra, statistics, trigonometry and
Time Second -:
In physics,we usethe SI units (International System)Electric Current caleulus
Ampere A(Cs)
for dataandcalculations

CLASSICAL MECHANICS
A. Classical or New tonian Mechanics The position of a .Newton's 1st Law: A body remains at rest or in G. Kinetic Energy & Work
body is given by an equation of motion with position, motion unless in uenced by a force 1. Kinetic energy, K: Kinetic energy is the energy of
velocity and acceleration as variables; mass is the 2. Newton's 2nd Law: Force and acceleration motion; mass, m and velocity, v: K = ½ mv²
measure of the amount of matter; the standard unit determine the motion of a body and predict future The SI energy unit is the Joule (J):
for mass is kg, 1 kg = 1000 g.; inertia is a property of positionandvelocity: F=ma 0R ZF=m a 1J=1kg ms
matter, and as such, it occupies space 3. Newton's 3rd Law: Every action is countered by an
2. Momentum, p: Momentum is a property of motion,
1. Motion along a straight line is called rectilinear; opposing action
de ned as the product of mass and velocity: p =mv
theequation of motiondescribestheposition of theE. Typesof Forces 3. Work (W): Work is a force acting on a body moving
particle and velocity for elapsed time, t
1.A body force acts on the entire body, with the force a distance; for a general force, F, and a body moving
a. Velocity (v): The rate of change of the displacement acting at the center of mass a path, s: W=J Fds
(6)withtime ()y =
A a. A gravitational force, F,, pulls an object toward
the center of the Earth: F = mg
For a constant force, work is the scalar

b.Acceleration (a): The rate of change of the product of the two vectors: force, F, and path, r:
b. Weight = F; gravitational force
dv Av W= Fdcos(0)= F•r
velocitywith time: a= At c. Mass is a measure of the quantity of material,
a & v are vectors, with magnitude and direction
c. Speed is the absolute value of the velocity; scala
independent ofg and other forces
2. Surface forces act on the body's surface
F 0
Maximum work
with the same units as velocity a. Friction, F,, is proportional to the force normal I Nowork
2. Equations of Motion for One Dimension (1-D) to the part of the body in contact with a surface,

Equations of motion describe the future position F:F,-pF. Dynamic Friction


4. Power (P) is energy expended per unit time:
i. Static friction resists the p= 4 Work A Work
(«) and velocity (v) of a body in terms of the initial
movement of a body time At
velocity (v), position (x) and acceleration (a)
ii. Dynamic friction slows Work= P(t)dt
a. For constant acceleration, the position is related
the motion of a body The Sl unit for power is the Watt (W):
to the time and acceleration by the following
For an object on 1W= 1 Joulelsecond = 1 J/s
equationofmotion: x() =x, + yt + ½at Work for a constant output of power:
horizontal plane: Cireular Motion
b.For constant acceleration, the velocity vs. time is W=PAt
given by the following: y,(0) =v,+at
F,- uF=mg
Netforce =F -F. H.Potential Energy & Energy Conseryation
c. If the acceleration is a function of time, the
equation must be solved using a = a(t)
F.CircularMotion 1. The total energy of a body, E, is the sum of kinetic,
1.Motion along a circular path uses K, & potential energy, U: E=K+ XU
B.Motion in Two Dimensions (2-D) polar coordinates: (r, 0 ) 2. Potential energy arises from the interaction with a
1.For bodies moving along ay Polar 2. Key Variables: potential from an extermal force
straight line, derive x- and y-
Potential energy is energy of position: U(r); the form
equationsof motion The distance from the
ofU depends on the force generating the potential:
Meter rotation center(centerof
Gravitation: U(h) = mgh
mass)
y=v,t+ha, t Electrostatic:U(r,J= 92
2. For a rotating body, use polar Tu
Polar: (,0) The angle between r and
Radian If there are no other forces acting on the system, E is
coordinates, an angle variable,xr cos., the (x) axis
constant and the system is called conservative
0, and r, a radial distance from y=r sine,
the rotational center O Radian/second The angular velocity I. Collisions&Linear
Momentum Collisions
1.Types of Collisions
C MotioninThreeDimensions (3-D)
a Radian/second The angularacceleration a. Elastic: conserve energy
1.Cartesian System: Equations of Spherical b. Inelastic: energy is lost as heat or
motion with x, y and z components deformation
2. Spherical Coordinates: Equations The circular motion arc 2. Relative Motion & Frames of
Meter
of motion based on two angles s=r (0 inrad) Reference: A body moves with
(0 and ) and r, the radialdistance velocity v in frame S; in frame S' the velocity is v'; if
from the origin v,' is the velocity of frame S' relative to S, therefore:
3.Tangential acceleration & velocity: y, = ro; a, = ra;
D. Newton's Laws of Motion v and a along the path of the motion arc
v=V'+
x=r sinpcos., 3. Elastic Collision
Newton's Laws are the core y=r sino sin),
principles for describing the motion cosp 4.Centripetalacceleration:a, =: a isdirected ConserveKineticEnergy: ½mv-% mv
toward the rotational center ConserveMomentum: Emy,-Emv, 2
of classical objects in response to ty+z?
forces; the SI unit of force is the a. The centripetal force keeps the body in circular 4. Impulse is a force acting over time
Newton, N: IN=1kg m/s²; the cgs unit is the dyne: motion with a tangential acceleration and velocity Impulse = F At or [F() dt
1 dyne = lg cm/s Impulse is also the momentum change: Píin - Pinit

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Classical Mechanics(continued) Qutckstuacly
J.RotationofaRigid Body IM.OscillatoryMotion WAVE MOTION
1.Center of Mass: The average" position in the 1. SimpleHarmonicMotion
body, accounting for the object's mass distribution a.Force: F--kAx A. Examples of Types of Waves
2. Moment of Inertia, I: The moment of inertia (Hooke's Law) •Transverse • Longitudinal
is a measure of the distribution of the mass about
the rotational axis: Emr?
b.PotentialEnergy:U, -+kAx'
c.Frequency of the oscillation:
m
Hooke's
Traveling
•Harmonic
• Standing
• Quantum mechanical
r, is the radial distance from m, to the rotational Law 1.General form for a transverse OR traveling wave:
axis Spring y= (k-vt) (to the right) OR y = f(x+ v) (to the left)
Sample I for bodies of mass m: 2. Simple Pendulum 2. General form for a harmonic wave:
rotating cylinder(radiusR): m R a. Period of oscillation: y=A sin (kx – ot) OR Standing Wave
twirlingthinrod(lengthL): m:
rotatingsphere(radiusR): mr T-2x y=A cos (kx – ot)
StandingWave:Multiplesof 2 ts
b.Frequencyofoscillation: the length of the oscillating material
Rotating Bodies Simple 4. Superposition Principle: Overlapping 312 2
Pendulum waves interact => constructive and
N. Forces in Solids & Fluids destructive interference

1.0, the density of a solid, gas or liquid: a. Constructive Interference: The


3. Rotational Kinetic Energy -I p=mass/volume= MV wave amplitudes add up to produce
The rotational energy varies with the rotational 2. Pressure, P, is the force divided by the area of a wave with a larger amplitude
velocity and moment of inertia, than either of the two waves Harmonie Wave
the forces acted upon: P = force/area
4. Angular force is de ned as torque, r. T = Ia = The SI unit of pressure is the Pascal, Pa: b. Destructive Interference: The
wave amplitudes add up to produce
rf(angular
acceleration
force) 1 Pa =1 N/ m²
a. Pascal's Law: For a uid a wave with a smaller amplitude
5. Angular momentum is the momentum associated Pascal's Law
than either of the two waves
withrotationalmotion:L- lo =rp=Jrvdm enclosed in a vessel, the 24
Torque is also the change in L with time: pressure is equal at all
B. Harmonic Wave Properties
points in the vessel
t=rF= dL
dt b.Pressure Variation
gular Wavelength(m) Distance between cycles
K. Static Equilibrium & Elasticity Momentum with Depth
P,; The pressure below
Period T (sec) Time to travel 1 cycle
1.Equilibrium is achieved when:
Ef= 0 Et 0
the surface of a liquid: P, = P, +pgh Frequencyr(Hz) Cyclespersecond: f= 1T
h is the depth, beneath the surface
The body has no linear or angular Angular
acceleration pis the densityof the water o(rad/s) -2r/T= 2xf
Frequency
P, is the pressure at the surface
2. Deformation of a solid body
Wave
a. Elasticity: A material returns Height ofwave
to its original shape after the force acting on it Pressure
Air 4 Amplitude
is removed Variation vvwwwwwpwwwSurthce |Speed v (m/s) Linearvelocityv =f
b. Stress & Strain
i. Strain is the deformation of the body Liquid
C. Sound Waves
i. Stress is the force per unit area on the body 1. Wave Nature of Sound: Sound is a compression wave
c. Hooke's Law: The stress is linearly c. Archimedes' Principle: An object of volume
that displaces the medium carrying the wave; sound cannot
proportional to the strain; stress = elastic V immersed in liquid with density p, feels a
travel through a vacuum
modulus x strain: buoyant force that tends to force the object
2. General Speed of Sound:
i. Linear Stress: out of the water: F, =p Vg
a. B is the bulk modulus, the volume compressibility of
Young's Modulus, symbolized Y Air the solid, liquid or gas
ii. Shape Stress: Archimedes" b.p is the density
w w 0 Surface
Shear Modulus, symbolized S Principle 3. For a Gas: v=
iii. Volume Stress: Liquid y=CJC, (the ratio of heatcapacities)
Bulk Modulus, symbolized B
4.Loudness - Intensity & RelativeIntensity
L. UniversalGravitation Loudness (sound intensity) is the power carried by a
3. Examine Fluid Motion & Fluid Dynamics
sound wave
a. Properties of an Ideal Fluid
a. Relative Loudness - Decibel Scale (dB):
M, .. Universal
Gravitation .. M, i.Nonviscous - minimal interactions
ii. Incompressible – the density is constant (aB) - 10os (.)
ii. Steady ow -no turbulence
1. Gravitational Force & Energy i. The decibel scale is de ned relative to the threshold
iv. At any point in the ow, the product of area of hearing, I,; P4,) = 0 dB
a.Gravitational
energy:U, MM, and velocity isconstant: A, v, = A, Y, ii.A change in 10 dB, represents a 10x increase in sound
b.Gravitational
force:F, - GM,M, b. Variable Fluid Density intensity, I
If the density changes, the following b. Doppler Effect
F, is a vector, along r, connecting M, and M,
equation described properties of the uid: The sound frequency shifts (I) due to relative motion
c. Acceleration due to Gravity, g: For an object
PAY, -P,A,Y, of the source of the sound and the observer or listener:
on the Earth's surface, F, can be viewed as
V, - speed of the observer; v, - speed of the source;
F -mg: g is theaccelerationdue togravityon ES
Varlable Fluld
v- speedofsound
the Earth'ssurface:g =9.8 m/s
Density i. Case 1: If the Doppler Efect
2. Gravitational Potential Energy, U,
+-) ->S
source of sound
a. The Earth's gravitational potential = A is approaching
Flow Through a Hose
>U =mgh the observer, the
b. Weight is the gravitational mD c. Bernoulli's Equation is a more general frequency increases:
force exerted on a body by the description of uid ow ii.Case #2: If the
Earth:Weight= F, =mg i. For any point y in the uid ow: source of sound is
moving away from
Weight is not the same P+%pvtpgy= constant the observer, the
90000000000000 ii.For a uid at rest (special case):
as 1mass frequency decreases:
Gravitational
Potential P,-P, -pgh
Energy

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THERMODYNANMICS
Thermodynamics is the study Thermodynamlcs e. Carnot's Law: For ideal gas: C, -C, = R c. Reversibile, isothermal expansion of an ldeal Gas
of the work,heat & energy of Carnot's Law is exact for monatomic gases; it against Pi gasexpands from V, to V, using an
aprocess must be modi ed for molecular gases in nite number of steps; the system remains in
IA. KeyVariables system) cquilibrium: W=n RT in
AE C.ldealGasLaw:PV n RT
This type of process gives the maximum work
1.The ldeal Gas Law
Heat: Q +Q added to the system a. Pressure, P: The standard unit is the Pascal (Pa), but
Single Step Expansion
the bar is more commonly used: I bar = 10' Pa
Work: W +W done by the system
b. Volume, V: The standard unit is the m, but the
Energy: E | System internal I liter, L, is more common: 1 L= 1 dm' Before Exxpansion

Enthalpy: H H-E+PV c. Temperature, T: The standard temperature unit is


absolute temperature, the Kelvin scale: T(K)
P
Entropy: S Thermal disorder d. Amount of gas, n: # of moles of gas (mol) P
Temperature: T Measure of thermal E e.R is a proportionality constant, the gas constant,
A er Expansion Work Performed
given the symbol R: R=0.083 L bar mo!K
Pressure: P Force exerted by a gas
2.Applications of Gas Laws
E. TheKineticTheoryofGases
Volume: V Space occupied a. Boyle's Law (constant temperature, T): Pressure is
1. Gas particles of mass, M, are in constant motion,
proportional to l/volume
with velocity, v, exerting pressure on the container
1.Thermodynamic variables are variables of state b. Pressure is proportional to temperature, with
and are independent of the process path; other volume xed 2. Equations for Energy of an Ideal Gas:
variables are path-dependent c. Charles' Law (constant pressure, P): Volume is E= My² and E=RT
2. Types of Processes: Experimental conditions can be proportional to temperature
a. Average Speed of a Gas Molecule:
controlled to allow for different types ofprocesses d. Avogadro's Law (constant P and T): Volume is

Condition Constraints Thermodynamic


proportional to the # of moles,
e. General Ideal Gas Law Application
V M
= /3RT
Result b.GasSpeed& Temperature: V, isproportional
i. Use PV =n RT to examine a gas sample under
Isothermal 4T= 0 AE=0, Q=w speci c conditions of P,V, n and T
to T;a changefrom T, to T,changesthespeed

AE =- w
Adiabatic=0
No heat ow PVT= constant
Boyle's Law Charles Law
c. Gas Speed & Mass: V is proportional to V

d. Kinetie Energy for 1.00 Mole of an Ideal Gas:


Isobaric AP 0 W- PAV
Fixed presure AH =Q
Pressure (Pa)
K-RT
Temperature (K)
AV = 0 AE =0 e. For a Real Gas: Add heat capacity and energy
IsochoricFixe volume W=0 terms for molecular vibrations and rotations
D. Enthalpy & Ist Law of Thermodynamics
F. Entropy& 2ndLaw ofThermodynamics
B. Temperature & Thermal Energy 1.W and Q depend on path of the process; however,
The 2nd Law of Thermodynamics is concerned with
1.Temperature measures thermal energy AEİSindependentofpath
the driving force for a process
a. The SI unit is Kelvin, absolute temperature: 2.1st Law ofThermodynamics:AE =Q-W
T(K) = TCC) + 273.15 a. The change in energy of the system (AE) is 1.Entropy, S
T is always in Kelvin, unless noted in the determined by the difference between the heat Entropy measures the thermal disorder of a
equation gained (Q) by the system and the work performed system:ds =
b. Zeroth Law of Thermodynamics: If two bodies, (w) by the system on the mechanical surrounding
Entropy is a state variable, like E & H:
#1 and #2, are separately in thermal equilibrium 3.Enthalpy, H AS (universe) = AS (system) + AS T.
with a third body, #3, then #1 and #2 are also in Enthalpy is a new state variable derived from the 1st (thermal reservoir)
thermal equilibrium Law of Thermodynamics at constantpressure: 2.2nd Law of Thermodynamics:
2. Thermal Expansion of Solid, Liquid or Gas H=E+ PV AH = AE + PAV For any spontancous process,
a. AH =Q for a process at constant pressure; the AS>0; AS 0 for a system s
a.Solid: aAT
difference between E and H is the work performed at equilibrium or for a reversible
by the process
b.Liquid: BAT process
Heat Flet
. Endothermic: Positive AH; the system absorbs
heat from the surroundings (EX: evaporation of 3.Examples of Entropy Changes
c.Gas:AV= CT) nR (Charles' Law) a. Natural Heat Flow: Heat ows from T,, o
liquid to gas; melting of a solid)
3. Heat Capacity, C i. Exothermic: Negative AH; the system releases b. Entropy & Phase Changes:
C depends on AT and Q, the heat lost or gained: heat to the suroundings (EX: combustion of fuel,
A H(change)
condensation of vapor to liquid) AS(change)
T (change)
C= A ORQ=CAT b.PhaseTransitions:solid - liquid - gasAphase
a. Speci c heat capacity is C per gram change coesponds to a change in enthalpy: solid>liquid positiveAS As,
i. Enthalpy of vaporization: AH, solid-→>liquid positiveAS AS
b. Molar heat capacity is C per mole
c. Two special experimental cases: i.Enthalpy offusion: AH,
c. Entropy & Temperature for an Ideal Gas:
i. Heat capacity for constantpressure, C: c. Enthalpy & VariableTemperature: AH=Jc,dT
AHis the keyvariable For constant C,: AH = C,AT
ST);AS- nC,in ()
Increasing T increases the disorder
ii.Heat capacity for constant volume, C,: 4.Examplesof Work: W =J Pdv
AE is the key variable a. P opposes the AV for an expansion; P causes the d. Entropy & Volume for an Ideal Gas
AV for compression; W depends on the path A gas expands from V, to V,:
d.ldealGas:C, = R ANDC, =R
b. Single step isobaric expansion from V,
i. The ratio of these two heat capacities is called y
to V, against an opposing pressure, P
sV): AS=nR In(
ii. For IdealGas:Y -167 W=(V,-V,)P.=AVPut The disorder of a gas increases if it expands

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Thermodynamlcs (continued) CurtekStudy
G. Heat Engines 2. The ef ciency of an engine, 1. is de ned as the
1.Thermal Engine: A heat
engine transfers heat, Q.
ratioofWdividedby Q:n0 P Carnot Cycle
2he
from a hot to a cold A
3. Idealized Heat Engine: The Carnot Cycle Chet
reservoir, to produce
work, W a. The Carnot Cycle consists of two isothermal B AT=0
a. The lst Law of steps and two adiabatic steps Thot
Thermodynamics states
i. For overall cycle:
that the work, W, must o.
equal the difference
AT = 0, AH = 0 and AS 0
D AT0
between the heat terms:
W=Q,Q
Thermal Engine
b. CarnotThermalEMciency= 1=l-
Qeotd
C
ELECTRICITY & MAGNETISM
c. For a material with dielectric constant x : 2.Ohm's Law: Current density, J, is in proportion

V) -v(vacuum) to the eld; o is called the conductivity: J = oE


3. Resistance
Electric Ficlds & Electric Charge F«)-F(vacuum) a. The resistance, R, accounts for the fact
that energy is lost by electron conduction;
A. Electric Ficlds & Electric Charge D. Capacitance&Dielectrics resistance is de ned as the voltage divided by
Examine the nature of the eld generated by an 1.A capacitor consists of two separatedelectrical the current: R =
electric charge and the forces between charges conducting plates carrying equal and opposite b. The SI resistance unit is the Ohm, 2
1.Coulomb, given the symbol C, is a measure of charge. A capacitor stores charge/electrical
c. I ohm () = Ivolt(V)
the amount of charge: potential energy l amp (A)
1 Coulomb = 1 amp• 1 sec 2. Capacitance, C, is de ned as the ratio of 4. Resistivity: The inverse of conductivity is
e is the charge of a single electron: charge, Q, divided by the voltage, V, for
resistivity, given thesymbol p : p =
e= 1.6022 x 10-1" C capacitor: C=;v is themeasuredvoltage;
Qis thecharge V 5.Voltage for current I owing through a
2. Coulomb's Law for electrostatic force, F
conductor withresistanceR: V= IR
F 4TE, 4 a. Energy stored in a charged capacitor:
6. Power Dissipation: Power is lost as I passes
3. Electrie Field, E, is the potential generated U=i Qv = cv through the conductor with R:
Power=VR= PR
by achargethatproduces F oncharge4,: b. Parallel plate capacitor, with a vacuum,
7. Resistors in Circuits: Certain groups of
E-Fa with area A, and spacing d:
resistors in a circuit are found to behave as a
4. Superposition Principle: The total F and E have
Capacitance:
i. C= . A single resistor
contributions from each charge in the system:
ii.Energy Stored: a.Forresistorsinseries: R R
F=EF. E-ZE
B. Sources of Electric Fields:Gauss's Law
U=AdE b.Forresistorsin parallel:R
ii. Electric Field:
1.Electric ux, , givesrisetoelectric eldsand
Coulombic forces
E-- Parallel Plate Capacitor
Two Resistors in Series Two Resistors in Parallel

RJR,
2.Gauss'sLaw: D= JE• dA -
Theelectric ux, ., dependsonthe totalcharge
c. Parallel plate capactor,
dielectrie material with R
in the closed region of interest

C. Electric Potential & Coulombic Energy


dielectric constant k,
with area A, spacing d R
C- KEa -KC,
1.Coulombic potential energy is derived from
R R+R
Coulombic force using the following equation:
C= vacuumcapacitor Resistors in Circuits r R,R
U=F dr i. Capacitors in Circuits: A group of
capacitors in a circuit is found to behave F. Direct Current Circuit (Da
a. Coulombic Potential Energy:
like a single capacitor

U 99
1. Goal: Examine a circuit containing hatf
4TEO i.CapacitorsinSeries: C resistors and capacitors; deternıine voli
current properties
b. Coulombic Potentia/Voltage ii.Capacitors in Parallel: Cu -Sc. 2. Key Equations & Concepts
i. The Coulomb potential, V(), generated by
q is obtained by dividing the U, by the EME:Thevoltageof acircuit )
Two Capacitors in Series Two Capacitors in Parallel electromotive force, denoted emf
testcharge,q: v(g) = 4T86T
U= V()|
c. Foranarrayofcharges,q, V,2V,
GlGl a. This voltage accounts for
V,, and the circuit voltage
emf= V,+ IR
2. Potential for a Continuous Charge Distribution: b. The battery has an intemal
Cio G+C,
V- g 4nE,
or
V,=Ir
3.Circuit Terminology
Capacitors in Circuits
3.The Dielectric Effect a.Junction:Connectionof es ore
a. Electrostatic forces and energies are diminished
-GG
Cat"C+C, conductors

by placing material with dielectric constant b. Loop: A closed conductor path

between the charges E. Current & Resistance: Ohm's Law c. Replace resistors in series or parallel with

b. Voltage and electrostatic force (V & F) depend 1.Current & Charge: The current, I, measures R
on the dielectric constant, k the charge passing through a conductor over a 1. Replace capacitors in series or parallel with

time; totalcharge,Q: Q =1t C


4

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Electricity & Magnetism(continued) QulckStuudy
4. Kirchoffs Circuit Rules 3.Magnetie Moment a. Gauss's Law is based on the fact that isolated
a. Constraints on the Voltage A magnetic moment, denoted M, is produced magnetic poles (monopoles) đo not exist
i. For any loop in the circuit the voltage must
bethesame: 2V =ZIR
by a current loop
a. A current loop, with current I and area A, I Faraday'sLaw -Electromagnetic Induction

ii. The energy must be generatesa magnetic moment of strength M:Faraday's Law: Passing a magnet through a current
conserved in a circuit loop M=1A loop induces a current in the loop

b. Constraints on the Current b. Torque on a loop: A loop placed in a magnetic


i. The current must balance at ,=l,+h cld will experience a torque, rotating the
every node or junction Constralnts on loop:= MB Faraday's Law
Current
ii. For anyjunction: 21-0
iii.The total charge must be conserved in the
circuit; the amount of charge entering and
leaving any point in the circuit must be
equal
7
G.MagneticFicld,B
1. Magnetic Field: A moving electric charge or 1.Faraday's Law of Induction
current generates a magnetic eld, denoted The EMF induced in a circuit is directly
by the symbol B; the vector B is also called proportional to the time rate of change of the
the magnetic induction or the magnetic ux magneticux, ,passing
throughthecircuit:
Torque on a Loop
density EMF- Eds AND EMF =
a. The SI unit for a magnetic eld is the Tesla, T dt
b. The SI unit for magnetic ux is the Weber, Wb
a. Special Case: Uniform eld B over loop of
4.U (magnetic): Magnetic potential energy area A; 0 is the angle formed by dA and B:
IT-Wm' N -*m arises from the interaction of B and M:
U (magnetic) = - M• B
EMF = (BA cos 0)
c. The CGS unit is the Gauss, G: 1 T= 10 G
5.Lorentz Force: A charge interacts with both b. Motional EMF: Moving a conductor of
d. For a bar magnet, the eld is generated from
E and B, the force is given by the following length 1 through a magnetic eld B with a
the ferromagnetic properties of the metal
expression:F = q E+qv•B speed v induces an EMF (B is perpendicular
forming the magnet
i. The poles of the magnet are denoted North/ a. B and E contribute to the force to the bar and to v): EMF = - Blv
South; the eld lines are shown in the gure b. The particle must be moving to interact with c. Lenz's Law: The direction of the induced
below the magnetic eld current and EMF tends to maintain the
original ux through the circuit; Lenz's Law
H. Sources of Magnetic Fields is a consequence of energy conservation
MagneticLines
of Force 1. Biot-Savart Law: Current generates a magnetic
eld J. Electromagnetic Waves
a. Given the current I and the conductor
Electromagnetic Wave
segment of length dl, the induced magnetic
eld contribution, dB, is described by the
following: dB
b. The total magnetic eld for the conductor is

e. For a current loop, the


by the motion of the charged particles in the
eld is generated
givenby: B= d'r
2. The magnetic eld strength varies as the inverse
current. square of the distance from the conducting 1. Electromagnetic waves are formed by tran s
element B and E elds
Lines of Force
3. Special Case - In nitely long straight wire: a. The relative eld strengths are de ned by
B(a) = ais the distance from the wire;
following
equation:c
I is the current; B, is inversely proportional to a b. The speed of light, c, correlates the mag
constaņt, H and electrie constant.
c=
c. In a vacuum, an electromagnetic wave,
wavelength, \, and frequency, f, travels
speed of light, c: c = f
2. Magnetic Force: F on charge, 4, d. X-rays have short wavelength, comparec
moving at velocity, v, in magnetic cld B: radio waves
F, qvB= qvBsin0 Biot-Savart Law e. Visible light is a very small part
spectrum
a. 0 is the angle between
vectors v and B K.Maxwell's Equations
i. For v parallel to B; F= 0 A•B
4. Ampere's Law: For a circular path around wire, Summarizethegeneralbehaviorof electricals
(0= 0, minimum force)
B magnetic elds in free space
ii. For v perpendicular to the total of the magnetic ux, B• dS, must be
B; F= qv B (0 = 2, consistent with the curent, I: f B • dS - 1. Gauss's Law for Electrostatics:
maximum force) A
Right-Hand 5.
Magnetic
Flux, . fEdA-
2 ii. The "right hand rule"
de nes the force Rule a.The magnetic ux, ,, associatedwith an 2. Gauss's Law for Magnetism:
direction area, dA, of an arbitrary surface is given by
$B• dA=0
b. Force on a conducting segment: For a current the following equation: o,-fB• dA; dA is
I passing through a conductor of length I in vector perpendicular to the area dA 3. Ampere-Maxwell Law:
a magnetic eld B, the force is given by: do
F=II|·B b. Special Case - Planar area A and uniform B fB•ds=H,I+H
i. For a general current path s: atangleI withdA: -BA cos 0
4.Faraday's
Law:fE: •dS -9
dt
F=1[ ds•B 6. Gauss's Law: The net magnetic ux through any
closed surface is always zero: B dA = (
ii.For aclosedcurrentloop: F=0

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BEHAVIOR OF LIGHT
A Basic Properties of Light B. Lenses & Optical Instruments 2. Key Varlables & Concepts
.Light exhibits a duality, having both wave 1.Lenses and mirors gencrate images of objects a. Constructive interference occurs when
wave amplitudes add up to produce a new
and particle properties Mirrer
wave with a larger amplitude than either of
2. Key Variables
the component waves
a. Speed of light in a vacuum, e
b. Index of refraction, n: y=y,ty,
The index of refraction, symbolizedn Ob)

is the ratio of the speed of light in a


vacuum divided by the speed of light in the ***
material: c(vacuum)
n 2. Lenses and mirrors are characterized by a
c(material)
number of optical parameters:
c. View light as a wave -focus on wave
a. The radius of curvature, R, de nes the
properties: wavelength and frequency
shape of the lens or miror; R is two times Constructlve Interference
i. For light as an electromagnetic wave:
thefocallength,f: R 2f b. Destructive Interference occurs when
iLight is characterized by its wavelength wave amplitudes add up to produce a new

("color"), or by its frequency, f |Lens & Mirror Properties wave with smaller amplitude than cither of
d. View light as a particle in order to the component waves; the wave amplitudes
understand the energetic properties of light Parameters + sign -sign cancel out
i. Energy is quantized in packets called
photons converging dìverging J' y=y,ty,
ii. The energy of photon depends on the lens lens
focallength
frequency, f with the proportionality concave convex
constant h, Planck's Constant: miror mirror
E(photon) =hf
virtual
3. Re ection & Refraction of Light objectdistancereal object
object
Destructive Interference
Re ection of Light
Incident virtual c. Huygens' Principle: Each portion of wave
s' image distance real image
Ray image front acts as a source of new waves
3. Di raction of light from a grating with
spacing d produces an interference patterm
object size erect inverted
0. governed by the following equation:
Re ected
d sin = mì, (m =0, 1,2, 3,.)
Ray n image size erect inverted 4. Single Slit Experiment:
For a wave passing through a slit of width
a. Law of Re ection: For light re ecting a, destructive interference is observed for:
b. The optic axis: Line from base of object
from a mirrored surface, the incident and sin 9 = m/a, (m =0, +l, +2, 13,..)
through center of lens or miror
re ected beams must have the same angle 5.X-ray diffraction from a crystal with atomic
with the surface normal: 0, = 0 c. Magni cation: The magnifying power of a spacing d gives constructive interference for:
lens is given by M, the ratio of image size 2 d sin 9 = mà, (m= 0, 1, 2, 3,...)
b.Refraction:
Light changes Refraction of Light toobject
size: M=
speed as it d. Laws of Geometric Optics
passes through i. The mirror equation: The focal length, Fundamental Physical Constants
materials with 6,: image distance and object distance are
Mass of
different indices described by the following relationship: m,9.11x10 kg

+-
Air Electron
of refraction;class S9
this change in Massof Protonm1.67x10" kg
speed bends the ii.The object and image distances can also be
light ray as it used to determine the magni cation: Avogadro
Constant
N, 6.022x10mo!
passes from n,
to n. Elementary
e. A combination of two thin lenses gives a 1.602x10-9 C
i. The angles of the incident and refracted Charge
lens with properties of the two lenses
rays are govened by Snell's Law:
Faraday
n, sin 8,=n, sin 0,; n, n,; indices of i. The focal length is given by the following 96,485 C mol!
Constant
refraction of two materials equation:=+
c.InternalRe ectance: sinl.; light 3. General Guidelines for Ray Tracing Speedof Lightc 3 x10 m s!
passing from material of higher n to a lower a. Rays that parallel optic axis pass through "r"
n may be trapped in the material if the angle b. Rays pass through center of the lens Molar Gas
K 8.314 JmotK
of incidence is too large unchanged Constant
c. Image: Formed by convergence of ray
4. Polarized Light: The eld of the
trac Boltzmann
electromagnetic wave is not spherically
d. Illustration of
k 1.38x10 JK-
Constant
symmetric (EX: plane (linear) polarized light, Ray Tracing
ray tracing for
circularly polarized light) a Converging Gravitation
a. One way to generate a polarized wave is by Lens
G 6.67x10!"m kg's
Constant
re ecting a beam on a surface at a precise
angle,called 0 C. Interference of Permeabilityof
Light Waves |Space
4nx 10'N A
b. The angle depends on the relative indices
1. Goal: Examine
of refraction and is de ned by Brewster's
constructive and Permittivity of
Law: tan 6,= 8.85 x 102 Fm
destructive interference of light waves | Space

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