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ICP Physics Final Exam Study Guide
Scientific Method
Steps: observe, hypothesize, gather information, experiment, analyze data, conclude, reconsider
Dependent vs. Independent Variable
Hypothesis vs. Theory vs. Scientific Law vs. bias
Controls vs. Constants
Accurate vs. Precise
Quantitative vs. Qualitative Measurements/ Research
Graphs: bar (groups; #) vs. line (trends) vs. circle/ pie chart (percentages); models
SI units: M – 106; k- 103; dk- 101; d- 10-1; c- 10-2; m- 10-3; - 10-6; n- 10-9; p- 10-12
M – mega; k- kilo; dk- decka; d- deci; c- centi; m- milli; - micro; n- nano; p- pico
SI base units: meter – length; kilogram – mass; second – time; ampere - current; Kelvin – temp.
Kelvin = 273 + oCelcius
Derived units: liter = (1 dm)3 = (10 cm)3 = 1000 cm3 = 1000 cc = 1000 ml; density = gram/ cm3
Forces, Motion & Speed
Newton’s laws of Motion (3)
1st; law of inertia – tendency of objects to resist change in motion;
“What’s moving stays moving; what’s stopped stays stopped.”; need for seatbelts
2nd; F = ma; kg m/s2= N = the net force acting on an object causes it to travel in same
direction as the net force until acted upon by another force; homerun
3rd; “For every action there is an equal and opposite reaction.” rifle recoil; rocket launch
Force = Newtons= push/pull that an object exerts on another object; balanced, unbalanced, net
Speed = distance traveled/ time of travel; meters/sec; average vs. instantaneous
Velocity = speed & direction of travel; Acceleration = (vf –vi)/t = m/s2 - can be (-) or (+)
Displacement = distance & direction of travel from origin; a2 + b2 = c2 for right triangles
Friction: static vs. sliding vs. rolling; microwelds
Air resistance – acts in direction opposite to that of object’s motion
*** Law of Gravitation = any 2 masses in universe exert an attractive force on one another
Gravity, electromagnetism, & strong & weak nuclear forces are the 4 basic forces of universe.
Gravitational acceleration on Earth is 9.8 m/s2. F= ma = (mass)(9.8 m/s2) = weight in Newtons
Objects of different masses or different sizes fall at the same acceleration in a vacuum.
Projectiles travel a parabolic path on Earth due to pull of gravity.
Centripetal acceleration = acceleration toward the center of curved or circular path
Momentum = p = mass x velocity = kg m/s; has direction because velocity has direction
Energy
= the ability to cause change; measured in joules = J =kg m2/s2
**Conservation of energy: energy can be neither created nor destroyed**
Potential vs. kinetic energy = energy of position vs. energy of motion
Potential energy: gravitational, elastic, or chemical bond; GPE = (mass)(9.8 m/s2)(height) = J
Kinetic energy: thermal, electrical, light, acoustic, motion; KE = ½ (mass)(velocity)2 = J
Nuclear energy = converting mass into energy via nuclear fusion (meld) or fission (division)
** Mechanical energy = potential energy + kinetic energy ** Mechanical energy is constant.
Sources of energy: fossil fuel, nuclear fission, solar, wind, water, geothermal, alternative fuels
Work
= transfer of energy that occurs when a force makes an object move = (Force)(distance)=Nm=J
Motion of object must be in the same direction as the applied force; picking up is, carrying isn’t
Power = rate at which work is done = work or energy/ time = Joules/ second = J/s = Watt = W
Machines
= any device that makes doing work easier; increase your force or distance or change direction
Effort vs. Resistance force; Effort vs. Resistance distance; Workin vs. Workout
Efficiency: % efficiency = (workout / workin) x 100%
Simple (6) vs. compound machines; ideal machines – no ideal machine because of friction
Simple: has only 1 movement: lever <wheel and axle; pulley> & incline plane <wedge; screw>
Lever: 1st class – pry bar; 2nd class – wheelbarrow; 3rd class – baseball bat
Compound machine: > 2 movements; can opener, car, engine, etc…
Thermal Energy
Temperature (avg. kinetic energy = K) vs. Thermal energy (kinetic + potential energy = J)
Different mass objects with same temperature have different thermal energy/ heat
Heat = transfer of thermal energy from something of higher temp to something at lower temp.
Specific heat = amount of heat needed to raise 1 kg of something 1 oC or 1 Kelvin= J/(kg K)=C
Water = 4184 J/(kg K); iron = 450 J/ (kg K); measured in calorimeter
Change in thermal energy = Q =(mass)(T final –T initial)(specific heat)= kg (K)(J/kg K)=J
Conductors vs. Insulators=Low specific heat vs.High specific heat; R value-measure insulation
Conductance (contact) vs. Convection (currents/waves) vs. Radiation (electromagnetic waves)
Radiant energy travels between molecules; is reflected, absorbed, or transmitted through matter
Heating systems: forced-air, steam or electric radiators; electric heaters; passive & active solar
Internal combustion engines; heat movers (frig, air conditioner, heat pump); sweat evaporation
Electricity
Conservation of charge = charge can’t be created or destroyed; static electricity;
Charge by contact; charge by induction; lightning = large static discharge – rips off electrons;
Thunder –due to masses of air expanding from lightning’s temperature (25,000 oC)
Conductors – allow excess electrons to pass through; insulator – impedes flow of electrons
Lightning rod allows electricity to be conducted to earth = “grounding”
Electroscope – detects presence of electricity
Current: Circuits – series vs. parallel; Batteries – wet vs. dry cell
Ohm’s Law = (Current)(Resistance) = Voltage difference; IR=V; (amperes)(ohms) = volts
Power = (current)(voltage difference) = Watts = (Amperes)(Volts)
Energy = Power x Time = kilowatt hours = kWh
Trace 3 supply routes of supplying electricity to residential homes
Magnetism
= properties and interactions of magnets; Greeks found magnetite mineral; Chinese also knew it
Magnetic field, poles, domains; compass needle - geographical vs. magnetic North –
Earth’s south magnetic pole is in northern Canada ~ 1500 km from geographical N pole.
Permanent magnets (Fe, Ni, Co) vs. induced magnets (electromagnets)
Electromagnetic induction: How do you make a magnet or make an electric current?
Electromagnets: galvanometer, stereo speaker, electric motor; switching poles;
Electric generators; water of windmills; transformers (step-up or step-down); AC vs. DC
Atoms
Parts: Nucleus (protons & neutrons) + electron cloud (electrons)
The # of protons defines the element; # of electrons defines the charge of the ion
Charges: protons (+); neutrons (0); electrons (-)
Forces: Strong – holds nucleus together; between protons, neutrons, & protons-n-neutrons,
Weak – holds individual protons or neutrons together; binds quarks together
Electrical – protons attract electrons; protons repel protons; electrons repel electrons
“Opposites attract; like repels.”
Radionuclear Energy
Discoverers: 1st was Henri Becquerel – uranium; Pierre & Marie Curie – radium & polonium
Decay emissions: alpha particles (), beta particles (), & gamma rays ()
: 2 protons + 2 neutrons; slow; can’t penetrate single sheet of paper; very damaging;
changes atomic # by –2 & atomic mass by -4


neutron converted to proton + electron is emitted from nucleus; faster; stopped by
aluminum foil or ½ inch plexiglass; changes atomic # by +1; damaging


 no charge or mass; fastest; stopped by lead sheets or concrete blocks; least damaging
Chain reaction; critical mass
Transmutation: changing 1 element into another with  or  decay
Half-life: amount of time for half the radiation to be lost; is at a constant rate; used to date age
of samples; 14C dates ancient junk < 50,000 yrs old; 235U dates rocks 106-7 yrs
Detection: Electroscope – arms come together with radiation present due to loss of electrons;
Geiger counter - clicks/lights occur with radiation completing electrical circuit
Bubble chamber – super hot liquid boils with radiation present
Cloud chamber – water or ethanol vapors form droplets with radiation present
Uses: Provide energy (nuclear reactor), weapons, fire alert, medical diagnosis/treatment
235
U – energy or weapons; 241Am – smoke detectors; 60Co – topical cancer treatment;
131
I – thyroid problems; 189Au & 192Ir – internal cancer treatment
Periodic Table
Groups – vertical rows; Periods – horizontal rows
Atomic number = # of protons of atoms = # of electrons of uncharged atom; identifies element
Atomic mass = # of protons plus the # of neutrons
Atomic mass minus the atomic number = # of neutrons; isotopes have differing # neutrons.
Waves
Transverse vs. compressional/ longitudinal vs. seismic; direction of matter in the waves differs
Parts of waves: crest, trough, compression, rarefaction, amplitude, wavelength, resting position
Frequency (Hertz – Hz = 1/sec = sec-1); wavelength inversely proportional to frequency
Reflection vs. refraction vs. diffraction; interference vs. standing waves vs. resonance
Sound waves: travels fastest through solids, slowest through gases/air; medium through liquids
travels fastest through warm matter; does not exist in vacuums
Intensity (amount of energy) vs. Loudness in decibels (human perception) vs. Pitch
Pitch (high vs. low – related to the frequency – do, re, mi, fa, so, la, ti, do)
Doppler effect: moving wave source wrt listener causes change in pitch or wave freq.
Acoustics – the study of sound
Echolocation: bats find loci from hearing the return of their echoes
Sonar: uses reflection of underwater sound waves to detect objects; submarines, whales
Ultrasound: high-frequency sound waves break up dirt build-up on jewelry/glassware,
destroy kidney stones, detect/ monitor pregnancy, some heart disease, & cancer
Electromagnetic waves
Wavelength inversely proportional to frequency
Gamma rays - shortest wavelengths & greatest frequency; radio- longest  & smallest 
Low to high  : Gamma rays, x-rays, UV-visible-Infrared, microwaves, radio waves
Colors: Low to high : violet, indigo, blue, green, yellow, orange, red
Radio waves: FM (frequency modulation) vs. AM (amplitude modulation)
FM (88-108 x 106 vibrations/sec) tends to be clearer than AM radio (1 x 106 Hz)
Mirrors & Lenses
Concave vs. convex vs. plane;double- vs.plano-;convexo- vs. concavo-; magnify vs. larger area