Physics Review Notes by Andrew Paolini

Final - May 16, Wheeler Auditorium, 8am

Know everything on the first page of any chapter

Chapter 1 – Energy and Power

• Energy- ability to do work
• Joules, Cal, cal, KWh, btu, quads
• Comparing Energies (energy per gram)
• Bullet @ speed of sound = .015
• Battery = .015-.15
• TNT = 1
• Choc. Chip Cookie = 8
• Gasoline = 15
• Hydrogen = 40
• Asteroid = 165
• U-235 = 30 million
• Relationship between gas/hydro
• Power = energy/time
• Hp, watts
• 1 hp = 1 kW
• Solar power = 1kW/m²
• Cost of getting energy
• Fossil fuel = 20 cents/kWh
• Batteries = $1000/kWh
• California energy crisis
• Kinetic energy
• Bullets, asteroids, smart rocks
• Demise of dinosaurs
• KE= ½ mv²

Chapter 2 – Atoms and Heat (thermodynamics)

• Speed of sound
• Pertains to lightning
• Different in different objects (faster in solid than gas)
• Sound can only move as fast as air/solid will permit it
• Difference between speed of sound and speed of light
• Thermal Expansion
• Air conditioners/refrigerators
• Freezing and Boiling point of water- in C, F, and K (know one and use calculator)
• Heat is the kinetic energy of molecules
• Brownian motion
• Dust is being hit by air molecules
• Dust will dance in the air because of the molecules
• Temperature = measure of heat
• Based on 0^th law of thermodynamics
• Put thermometer in room it will heat up to room temperature
• 1^st law = conservation of energy
• 2^nd law = nothing converts 100% of its energy
• 3^rd law = Absolute Zero
• zero movement in molecules
• Insulators vs conductors
• Coffee cups aren’t made of metal (metals are good conductors)
• Air and plastic are good insulators
• Phases – solids, liquids, gasses, plasmas
• Ideal Gas Law
• Air Bag – basically a little explosion

Chapter 3 - Gravity

• Everything that has mass attracts everything else that has mass
• How massive and how far away?
• Closer to something massive, the more the force is felt
• Newton’s 3^rd Law – Every action has an equal and opposite reaction
• Orbit –continuous falling at the same rate due to gravitational pull
• Don’t fly off, don’t fall in – an equilibrium
• 8 km/s for earth
• Escape velocity – 11 km/s for earth
• Different types of orbits
• LEO – spy satellites
• MEO - GPS
• HEO – geosynchronous, TV
• Searching for oil by using gravity detection devices
• Equations
• V=gt
• Gravity = 9.8 m/s
• D = ½ gt²
• F=ma (Newton’s 2^nd law)
• Momentum – M1V1 = M2V2
• Rail gun (appears in multiple chapters)
• Centripetal acceleration
• Skyhook
• Ion Rockets – why they would be better than current rockets
• Airplanes and Helicopters – push air down
• Hot Air Balloons – use less dense gas to float in air
• Submarines – Use air to float or sink in water

Chapter 4 – Radiation

• Radiation sickness
• How radiation relates to cancer
• Linear hypothesis
• Atom contains nucleus, protons, neutrons, quarks, gluons, strings, electrons
• Not all elements are the same
• Element is named by number of protons
• Isotopes
• Hydrogen – proton and electron
• Add neutron and get deuterium
• Add second neutron and get tritium (exit signs)
• Isotopes are unstable (deuterium)
• Cloud chamber
• Chernobyl, Hiroshima
• Types of radiation
• Alpha rays – 2 protons, 2 neutrons (pretty big size, small velocity)
• Beta rays – electrons
• Gamma rays – really bad, lots of energy
• Neutrons
• X-rays
• Cosmic rays
• Fission fragments
• Half-life
• Time it takes for ½ of something’s atoms to decay into something else
• C-14 = 5730 years
• K-Ar dating
• Helium is created in the ground due to ration
• Fission
• Fusion – source of sun’s energy

Chapter 5 – Nukes

• Chain Reactions
• Chess board, nuclear bomb, development of a fetus, cancer, population bomb, PCR (know PCR and chain reactions as they are some of Muller’s favorites), illness and epidemics, computer viruses, avalanches, lightning, compound interest, Moore’s law, trees
• Why its hard to make nuclear bomb
• Realize nuclear energy is millions of times more powerful than TNT
• Splitting one nucleus is not enough, have to figure out the concept of chain reaction
• Some elements decompose by emitting a neutron
• These elements also are triggered to decompose when a neutron hits them
• Need an element that emits 2 neutrons (i.e. U-235)
• Uranium
• .7% is U-235 (important one)
• 99.3% is U-238
• enrichment is getting as much U-235 as possible
• Calutron
• Nuclear power plants need about 3% U-235
• Nuclear bombs need higher percentage
• Plutonium 239
• Releases 3 neutrons
• “most dangerous substance on the earth”
• breeder reactors
• Plutonium 240
• Emits radiation which prevents chain reaction
• Implosion is solution for Plutonium
• Yuca Mountain
• China Syndrome

Chapter 6 – Electricity and Magnetism

• Electric charge = 1.6 x 10^-19 coulombs
• Electron (-), proton (+), neutron (=)
• Electrons moving together is a current
• Resistance is electrons running into other things which cause them to give up their energy in the form of heat.
• Conductors (metals like copper)
• Semi-conductors (apply right voltage then electrons will flow)
• Insulators (will conduct with large voltage)
• P=IV
• Power is dangerous
• High voltage with no current is not dangerous
• High current with no voltage is not dangerous
• Current is measured in amps
• Voltage is measured in volts
• Moving charge makes magnetism
• Permanent magnets
• Loadstone (used in compasses)
• Fe, Co, Ni, Cr
• Samarium (rare earth magnets), used in ear bud headphones
• Magnetism is used in storing information based on north or south charge
• AC vs DC
• DC came out first from Edison
• AC came second from Tesla
• Makes use of electromagnetism by using a transformer
• Transformer – 2 coils of wire with different # of coils
• Electromagnetism
• Electric generator
• Dynamo
• Earth is a magnet (poles flip 2 times/million years)
• Magnetic levitation
• Finding subs, metal detectors, rail guns

Chapters 7 – Waves

• Sofar

• Maurice Ewing - Military
• Mogul
• SOSUS
• Terms
• Frequency
• Velocity = Frequency x Wavelength
• Wavelength
• Amplitude
• Period = Wavelength/Velocity
• Types of waves
• Longitudinal
• Transverse
• Surface waves
• Tsunamis
• Waves bend
• Ground is hot, Middle air is cold, Atmosphere is hot
• Sound channel
• Temperature inversion
• Earthquakes
• Waves can cancel and reinforce
• Noise canceling earphones
• Interferences
• Beats = frequency1-frequency2
• Doppler shift

Chapter 8 –Light

• Fiber optic
• Cones in the eye (Muller just had eye surgery)
• Different lenses, the iris, etc
• Multispectral cameras
• Spy satellites
• Laser induced fusion (transport a lot of power somewhere using light)
• Bandwidth – light can have a higher frequency than electricity
• Bandwidth = Frequency
• Spectrum of visible light ROYGBIV
• Colorblindness is missing one of the three cones
• Most sunlight is green, green is the peak energy
• Pinhole cameras (eyes is basically a pinhole camera)
• Mirrors and corner reflectors (stop signs, red eye, stealth and radar)
• Slow light, refraction
• Index of refraction (symbolized by n which = c/v)
• Spear fishing
• Mirages
• How lenses work
• Dispersion
• Prism
• Diamonds vs CZ (CZ are better at dispersion)
• Rainbows
• Nearsightedness and farsightedness
• Diffraction = Wavelength x Distance to opening / Size of opening
• Holograms
• Polarization
• LCD screens

Chapter 9 – Invisible Light

• IR
• Night vision
• Power radiated = T^4
• Red hot, white hot, blue hot
• Tungsten converts 16% to light
• Pit vipers, mosquitoes, stinger missles
• Greenhouse effect and global warming
• UV
• Black lights
• Fluorescence
• Sunburn
• Freon and CFCs
• Linked to cancer
• Ozone layer
• Radiowaves, microwaves, x-rays, gamma rays
• Medical imaging
• X-rays
• NMR or MRI
• CAT
• PET
• Ultrasound (not electromagnetic)

Chapter 10 – Quantum

• Lasers
• Solar cells
• Transistors
• Computer circuitry
• Digital cameras
• Superconductors
• Einstein equation E=hf
• Bohr (everything is a wave, including electrons)
• Band gaps and devices that use it
• Xerox makes use of photoelectric effect
• Semiconductors
• CDs, DVDs
• LED, diodes, AC to DC converters
• Superconductors
• Electron microscopes
• Tunneling – fusion in the sun
• Quantum computers

Chapter 11 – Relativity

• Classical physics is before quantum and relativity
• Time, gravity and velocity and independent
• Electromagnetism does not match up with Newtonian physics
• Aether
• Hypothetical medium, a vacuum that light is waving in
• Method to detect how fast we are moving with respect to Aether
• Michaelson-Morley Experiment
• Speed of light is constant
• Einstein says change concepts of space and time
• Speed of light is constant regardless of who is observing
• No experiment that can detect constant motion without reference to an outside object
• Time dilation – f= Sq rt. (1- beta²), beta²=r²/c²,
• Length contraction
• Relativity of simultaneity
• Velocity addition
• Twin paradox (twin that accelerates is younger)
• Relativistic energy and momentum
• Rest energy = mc²
• Relativistic Doppler shift (universe is expanding
• Neutrinos can decay
• General relativity
• Inside enclosed spaceship, cannot tell gravity from rockets simulated as gravity
• Gravity and acceleration affect time
• Black holes – escape velocity > c

Chapter 12 – Universe

• Big Bang
• 14.5 billion years ago the universe came about from a ball of energy turning into mass
• Universe is expanding therefore it must once have been smaller
• When energy was converted into mass, it was luminous
• 10^12 Kelvin when universe started
• This is now a 3K glow due to red shift
• Asymmetric pair production is possible
• More particles than anti-particles
• Universe is 75% H and 25% He
• Stars and Planets
• Big clouds of hydrogen and helium
• Cloud accelerates toward dense spots and becomes hotter
• At 10^6 K fusion occurs
• Stars evolve then die
• Solar system consists of sun, planets, moons, comets, asteroids
• Elements heaver than Fe are created in supernova
• Galaxies and Clusters
• Stars form in groups – galaxies
• Milky Way is 100,000 light years across
• 90% of galaxy is dark matter
• MACHOs and WHIPs are dark
• Galaxies come in clusters and clusters come in super clusters
• Our cluster is called the local group consisting of the Milky Way and Andromeda
• End of universe
• Expand then fall in on ourselves, Big Crunch
• Expand slower and slower, Big Chill
• Expand but speed up due to dark energy
• Past exams, common topics
• What’s in a solar system?
• Drake equation – SETI program
• Dark matter, how much, how do we know
• What is the sun’s energy source?
• What do elements come from?
• Everything up to Fe is stars, Fe and after is supernovas
• Doppler shift, coming towards is blue shift, away is red shift
• Galaxy is expanding, dark energy
• 14.5 billion years is approx. earth age
• No middle or edge to universe