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Study Guide- Bare Bones list Physics Comprehensive Exam 2014
1 Made by Ashley Thomas
I. Scientific Measurement
Metric Units
S.I. English
Length Meter (m) Feet (ft.)
Mass Kilogram (kg) Pound (lb.)
Weight Newton (N) Ounce (oz.) or pound (lb.)
Time Seconds (s) Seconds (s)
Volume Liter (L) Gallon (gal)
Temperature Kelvin (K) or Celsius ( ) Fahrenheit ( )
Metric Prefixes
Name Abbreviations Number Association
Name Abbreviations Number Association
Pico p Tera T Nano n Giga G Micro Mega M Mili m Kilo k Centi c Hecto h Deci d Deka Da
Know how to:
o Convert between metric units (including with prefixes)
II. Position, Velocity, and Acceleration
Definitions related to motion
o Reference point: A coordinate system used to define a motion.
o Position: Where an object is precisely located.
o Motion: Movement relative to a fixed point.
o Speed: The measure of how fast something is moving. Vector quantity.
o Velocity: Speed with direction. Vector quantity.
o Acceleration: Rate of change of velocity.
Equation for speed and units
o Equation: speed equals distance divided by time
o Units: meters per second (m/s)
Average speed formulas with distance and time
o MEMORIZE:
Difference between instantaneous and average velocity
o Instantaneous Velocity: The velocity that something is traveling at any one instance.
o Average Velocity: Total displacement over a time interval.
o If the object is traveling with constant velocity its instantaneous and average velocities will
be the same.
Difference between positive and negative acceleration
o Positive acceleration is acceleration in the direction of velocity.
o Negative acceleration is acceleration opposite the direction of velocity.
Study Guide- Bare Bones list Physics Comprehensive Exam 2014
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Graphing position vs. time and relation to velocity and acceleration
o See Attachment 1
Graphing position vs. time and how this illustrates acceleration
o See Attachment 1
Equation for acceleration
o MEMORIZE:
o Units: m/
Instantaneous velocity given initial velocity, acceleration, and time
o MEMORIZE:
Differentiate between speed and velocity
o Speed: Distance of an object over time
o Velocity: change in speed with direction.
Know how to:
o Calculate resultant velocity (parallel vectors only )
o Calculate acceleration
o Solve for any variable in the V final equation
III. Forces and Newton’s 1st and 2nd laws of motion
Newton’s first law of motion
o An object at rest will stay at rest, and an object in motion will stay in motion at a constant
velocity, unless acted upon by an unbalanced force.
o Inertia: The tendency of an object to resist changes in its velocity, whether in motion or
motionless.
o Mass is the measure of inertia in response to an effort made to stop it, start it, ect.
Mass and weight
o Definition of mass as inertia: The proportional force to cause a unit of acceleration.
o Mass (as a quantity of matter: Quantity of matter in an object. The amount of “stuff” in an
object.
o Weight: The magnitude of the force of gravity acting on an object.
o Mass is the amount of “stuff” but weight is the amount of “stuff” with the force of gravity
acting on it.
Newton’s second law of motion
o The acceleration of an object is directly proportional to the net force acting on the object, is
in the direction of the net force, and is inversely proportional to the mass of the object.
o Simplified Version of 2nd law: Net force is equal to the mass times the acceleration.
o MEMORIZE: F=ma
Force
o Force: Any influence that tends to accelerate an object. More simply any kind of push or
pull.
o Net Force: The combination of all the forces that act on an object.
o Units: Newton
o Derive units with SI units:
Study Guide- Bare Bones list Physics Comprehensive Exam 2014
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Equilibrium
o Equilibrium: A state of balance.
o Static Equilibrium: When all the forces acting on an object are balanced and the object is not
moving.
o Dynamic Equilibrium: When all the forces acting on an object are balanced and the object is
moving.
o Static and dynamic equilibrium both involve objects in a state of equilibrium but in dynamic
the object is in motion, but moving with a constant velocity.
Balanced vs. unbalanced forces
o Balanced Force: Equilibrium, the sum of forces is equal to zero.
o Unbalanced Force: Not in equilibrium, the sum of forces is equal to acceleration times mass.
Definition of normal force
o Normal Force: A force perpendicular to the surface, 90 degrees.
Frictional force
o Friction Force: A force opposite to motion, and parallel to the ground that it is traveling on.
o Causes: FRICTION!!!!
Hooke’s law
o Distance of stretch or squeeze (expansion or compression) of an elastic material is directly
proportional to the applied force.
o MEMORIZE:
Know how to:
o Calculate weight given mass and acceleration due to gravity (W=mg)
o Solve for any variable in the “F=ma” equation
o Calculate net force using Newton’s second law of motion.
o Calculate net force given parallel forces, including applied force and tension.
o Calculate, Hooke’s law, using the formula and solve for any variable.
IV. Newton’s 3rd law of motion
Newton’s third law of motion
o For every action there is an equal and opposite reaction
o Understand the action and reaction relationship.
V. Momentum
Momentum
o Momentum: inertia in motion. The product of the mass and the velocity of an object. Has
magnitude and direction and therefore is a vector quantity.
o MEMORIZE: p=mv
o The relationship between inertia and momentum is momentum is inertia but in motion.
Impulse: don’t have to know for common section of pre-comp,
o Impulse: the product of force and the time interval during which the force acts. Produces
change in momentum.
o MEMORIZE: j= j=Ft
o Be able to solve for any variable.
Definition of conserved quantity
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o Conserved: Term applied to a physical quantity, such as momentum, energy, or electric
charge, which remains unchanged during interactions.
Conservation of momentum:
o In the absence of a net external force, the momentum of an object or system of objects is
unchanged.
Analyze more advanced situations involving impulse and momentum
o See “know how to”
Know how to:
o Solve for any variable in the momentum equation
o Solve problems of collisions using the conservation of momentum
o Calculate final velocity after a collision between two objects that stick
o Use Newton’s second law, momentum, acceleration, and time to solve for any variable using
two equations.
VI. Energy
Work
o Work: The product of the force on an object and the distance through which the object is
moved (when force is constant and motion is in a straight line in the direction of force)
o Work is done when a force produces motion.
o MEMORIZE: W=Fd
o Units: Joule (J)
o Derive units with SI units:
Energy
o Energy: Anything that can change the condition of matter. Commonly defined circularly as
the ability to do work;
o Units: Joule (J)
o Derive units with SI units:
Mechanical energy
o There are two types of mechanical energy, which are potential and kinetic.
o Potential Energy: Energy of position, usually related to the relative position of two things,
such as a stone and the earth (gravitational potential energy), or an electron and a nucleus
(electric PE). Raised position (gravitational) or a condition (e.g. compressed springs , rubber
bands, Elastic PE)
o Gravitational Potential Energy: The potential energy of a body due to elevated positions.
o Kinetic Energy: Energy due to motion.
o Energy storage: _____________________________________________________________
___________________________________________________________________________
___________________________________________________________________________
o Spring Energy: Energy due to a spring.
Energy calculations
o MEMORIZE:
o MEMORIZE:
Study Guide- Bare Bones list Physics Comprehensive Exam 2014
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o MEMORIZE:
Law of conservation of energy
o Energy can’t be created or destroyed.
o Only true if only conservative forces (e.g. gravitational energy, spring forces, electric forces)
act on the objects, no non-conservative forces (e.g. Friction, applied, and tensional forces).
o
Work-energy theorem (work- kinetic energy theorem)
o
o Speed will increase if the work is positive
o Speed will decrease if the work is negative
Know how to:
o Solve for any variable in the work formula
o Solve for any variable in the formulas from the “energy calculation” section
o Calculate the total energy of a simple system of a moving object or spring system at a given
height.
VII. Vibrations and Waves
Waves
o Wave: a disturbance that repeats regularly in space and time and that is transmitted
progressively from one place to the next with no net transport of matter. A disturbance
that travels through a medium from location to another.
o Medium: A substance (solid, liquid, gas, or plasma) that can transport waves.
o Frequency: For a vibrating body or medium, the number of vibrations per unit of time.
For a wave, the number of crests that pass a particular point per unit of time.
o Unit of Frequency: Hertz (Hz)
o Period: In general, the time required to complete a single cycle. For vibrations and
waves, the time required for one complete cycle, equal to 1/frequency.
o Unit of Period: Seconds
o Longitudinal Wave: A wave in which the individual particles of a medium vibrate back
and forth in the direction in which the wave travels. (Ex. Sound)
o Transverse Wave: A wave with vibration at right angles to the direction the wave is
traveling. (Ex. Light consists of transverse waves)
o Mechanical Wave: ________________________________________________________
________________________________________________________________________
________________________________________________________________________
o Electromagnetic Wave: An energy- carrying wave emitted by vibrating charges (often
electrons) that is composed of oscillating electric and magnetic fields that regenerate
one another. (Radio waves, microwaves, infrared radiation, visible light, ultraviolet
radiation, x-rays, gamma rays)
o Be able to identify and measure amplitude and wavelength: see Attachment 3
o Be able to identify crest, trough, equilibrium line, rarefaction, and compression: see
Attachment 3
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Wave Calculations
o MEMORIZE:
or
o See know how to
Definition of Standing Wave: A stationary wave pattern formed in a medium when two sets of
identical waves pass through the medium in opposite directions. The wave appears not to be
moving.
Constructive vs. Destructive Interference
o Constructive: Combination of waves so that two or more waves overlap to produce a
resulting wave of increased amplitude.
o Destructive: Combination of waves so that crest parts of one wave overlap trough parts
of another, resulting in a wave of decreased amplitude.
o Interference: result of superposing different waves, often of the same wavelength.
Know how to:
o Calculate frequency based on waves per unit of time.
o Calculate period based on frequency and vice versa.
VIII. Sound
Definition of Sound: Longitudinal wave phenomenon that consists of successive compressions
and rarefactions of the medium though which the wave travels.
Properties of sound waves
o Energy that makes matter vibrate
o Created through vibrations
o Fastest in solids, slowest in gases
o Warm air transmits sound faster
o Effected by: type of medium and temperature
o You see it before you hear it!
o Has frequency and pitch
Pitch: highness or lowness of a sound and depends on frequency.
o Has loudness and intensity
Intensity: depends on the energy in a sound wave.
Loudness: Human perception of intensity.
Speed of sound: m/s
Definition of Intensity: Power per square unit meter carried by a sound wave, often measured in
decibels. Depends on the energy in a sound wave.
IX. Gravity
Newton’s Law of Universal Gravity
o MEMORIZE formula:
o Be able to calculate the force between two objects
X. Electrostatics
Electrostatics
o Electrostatics: The study of electric charges at rest, as opposed to electrodynamics.
Electricity at rest.
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o Electric Charge: Fundamental electric property to which the mutual attractions or
repulsions between electrons or protons is attributed. Units are columbs.
o Interaction between like and unlike charges
Like charges repel.
Unlike charges attract.
o Electrical Force: A force that one charge exerts on another. When the charges are the
same sign, they repel; when the charges are opposite, they attract.
Conservation of charge
o Electric charge is conserved.
o Net charge of an atom:
Balanced: no charge
Unbalanced: has a charge
Ions: a charged atom. Either positive or negative.
Conductors vs. Insulators
o Conductor: Electric charges move more freely. A material through which heat can be
transferred. Material, usually a metal, though which electric charge can flow. Good
conductors of heat are generally good electric charge conductors.
o Insulator: Electric charges do not move freely. A material that is a poor conductor of
heat and that delays the transfer of heat. A material that is a poor conductor of
electricity.
Charging Methods
o Conduction: In heat, the energy transfer from one particle to a particle within certain
materials, or from one material to another when the two are in direct contact. In
electricity, the flow of electric charge through a conductor.
o Induction: The charging of an object without direct contact. Redistribution of electric
charges in and on objects caused by the electrical influence of a charged object close by
but not in contact.
o Friction: Similar to charging by conduction; the objects are charged by creating friction,
or rubbing the two together.
Electric Field
o Definition: A force field that fills the space around every electric charge or group of
charges. Measured by force per charge (Newton/coulomb)
o Cause of: Exists around charged objects.
o Direction of: Toward the negative charge.
Definition of electric potential energy
o The energy a charge has due to its location in an electric field.
Definition of electric potential
o Electric potential energy (in joules) per unit of charge (in coulombs) at a location in an
electric field; measured in volts and often called voltage.
Coulomb’s Law: The relationship among electrical forces, charges, and distance: the electrical
force between two charges varies directly as the products of the charges (q) and inversely as the
Study Guide- Bare Bones list Physics Comprehensive Exam 2014
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square of the distance between them. (k is the proportionally constant 9*10^9 N*m^2/c^2) If
the charges are alike in sign, the fore is repulsive; if the charges are unlike, the force is
attractive.
Know how to:
o Solve problems using Coulomb’s law
XI. Electric Current
Electric current
o Definition: The flow of electric charges that transport energy from one place to another.
o Units: amperes (amps)
Potential difference (voltage)
o Definition: The difference in electric potential (voltage) between two points. Free charge
flows when there is a difference, and will continue until both points reach a common
potential.
o Units: Volts
Electrical resistance and resistor
o Electrical Resistance: The resistance of a material to the flow of electric charge through
it.
o Resistor: A device in an electric circuit designed to resist the flow of charge.
o Unit of Electrical Resistance: Ohms ( )
o Understand why dissipated electrical energy is converted into heat.
Electrical energy is often transformed into other types of energy, heat being one
of those types.
o Explain resistance in terms of interaction between charge carriers and fixed atoms
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
Ohm’s Law: Current in a circuit is directly proportional to the voltage impresses across the
circuit, and is inversely proportional to the resistance. I=V/R
o MEMORIZE: I=V/R
Alternating Current
o Definition: Electric current that rapidly reverses in direction. The electric charges vibrate
about relatively fixed positions.
o Properties: The current flows in one direction, and then the other.
o Purpose: air conditioning units use AC, most residential and commercial circuits, long-
distance transmission. Transfer energy quietly, flexibly, and conveniently from one place
to another.
o Know that AC has a periodic property (frequency) and its effect on the subatomic level
Electrons in the circuit are moved first in one direction and then in the opposite
direction.
Study Guide- Bare Bones list Physics Comprehensive Exam 2014
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Direct Current (DC) vs. Alternating Current (AC)
o Direct Current: Electric current whose flow of charge is always in one direction.
o Alternating current: see above
o Both have the purpose of transferring energy quietly, flexibly, and conveniently from
one place to another.
Electric Circuits
o Electric Circuit: A network consisting of a closed loop, giving a return path for the
current.
o Series Circuit: Electric circuit with devices connected in such a way that the electric
current through each of them is the same.
o Parallel Circuit: Electric circuit with two or more devices connected in such a way that
the same voltage acts across each one and any single one completes the circuit
independently on the others.
o MEMORIZE: formula for series resistance:
o MEMORIZE: formula for parallel resistance:
o Know the symbols for battery, resistor, lamp, wire, and switch
o Recognize an open vs. closed circuit
Electric Power: NOT ON COMP!!!!
Know how to:
o Apply the equation for current
o Solve for any variable in the Ohms law equation
XII. Magnetism
Magnetic Field
o Definition: A region of magnetic influence around a magnetic pole or a moving charged
particle.
o Cause: Caused by moving electric current
o Relationship between electric current and magnetic fields: when moving, electric
current caused magnetic field.
Definition of magnetic force
o Between magnets: the attraction of unlike magnetic poles for each other and the
repulsion between like magnetic poles
o Between magnetic field and moving charged particle: a deflecting force due to the
motion of the particle. The deflecting force is perpendicular to the magnetic field lines
and the direction of motion. This force is greatest when the charged particle moves
perpendicular to the field lines and is smallest (zero) when it moves in parallel to the
field lines.
Magnetic poles
o Definition: one of the regions on a magnet that produces magnetic forces.
o Interaction between like and unlike poles
Like poles repel
Unlike poles attract
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Magnetic domains
o Definition: microscopic cluster of atoms with their magnetic fields aligned.
o Behavior: Perfectly magnetized and made up of billions of aligned atoms.
Definition of electromagnetism and electromagnet
o Electromagnetism: Electricity and magnetism co-exist and the study of both electricity
and magnetism is called electromagnetism. Electricity and magnetism are known to be
components of the united theory of electromagnetism.
o Electromagnet: Magnet whose magnetic properties are produced by electric current. A
current-carrying coil of wire is known as an electromagnet. An electromagnet is a type
of magnet in which the magnetic field is produced by the flow of electric current. The
magnetic field disappears when the current is turned off.
XIII. Properties of Light
Sources of light
o Natural: sun, stars, supernovas, lightning, bioluminescence, nuclear
o Artificial sources: chemical, electric power, combustion, nuclear
Light as an electromagnetic field
o The energy field created by electricity and magnetism can oscillate and support waves
that move or electromagnetic waves.
o The visible part of the electromagnetic spectrum
Speed of light:
o C= F
o 3*10^8 m/s
MEMORIZE: E=hF and the above equation
Transparent vs. opaque materials
o Transparent: A term applied to materials that allow light to pass through them in
straight lines.
o Opaque: A term applied to materials that absorb light without re-emission, and
consequently do not allow light through them.
Reflection and refraction
o See definitions related to reflection and refraction for, guess what, definitions of the
terms!
Definitions related to reflection and refraction
o Reflection: The return of light rays from a surface in such a way that the angle at which a
given ray is returned is equal to the angle at which it strikes the surface. When the
reflecting surface is irregular, the light is returned in irregular directions, this is known as
diffuse refection. In general, the bouncing back of a particle or wave that strikes the
boundary between two media.
o Refraction: Bending of an oblique ray of light when it passed from one transparent
medium to another. This is caused by a difference in the speed of light in the
transparent media. In general, the change in direction of a wave between two media in
which the wave travels at different speeds.
Study Guide- Bare Bones list Physics Comprehensive Exam 2014
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o Virtual Image: An image formed by light rays that do not converge at the location of the
image. Mirrors, converging lenses, used as magnifying glasses, and diverging lenses, all
produce virtual images. The image can be seen by an observer, but cannot be projected
onto a screen.
Law of reflection: The angle of incidence for a wave that strikes a surface is equal to the angle of
reflection. This is true for both partially and totally reflected waves.
Understand the path taken by refracted light
o Slower medium to faster medium: light bends away from the normal surface.
o Faster medium to slower medium: light bends toward the normal surface.
Understand why a prism is able to separate light
o Prism: A triangular solid of transparent material such as glass that separates incident
light by refraction into its component parts known as the visible light spectrum.
Definition of total internal reflection
o The 100% refection (with no transmission) of light that strikes the boundary between
two media at an angle greater than the critical angle.
o The phenomenon that happens when a wave hits a medium at an angle larger than its
critical angle.
Know how to:
o Calculate photon energies using the equation E=hf
o Solve simple problems by combining E=hf and c= f
XIV. Astronomy
See the handouts Mr. Clark gave to us: bare bones and astronomy HW answers!
My notes from astronomy PowerPoint
o Solar spectrum: the sun emits radiation at all wavelengths
50% visible
40% Infrared radiation
10% Ultra Violet radiation (UV Rays)
o The sun is a main sequence star, and generates its energy by nuclear fusion of hydrogen
nuclei into helium.
o Nuclear Fusion
When two or more atomic nuclei collide at a high speed
After the collision= new type of atomic nucleus
Mass is not conserved
Converted to photons
Powers active or main-sequence stars
o Light as a wave
Determine: surface temperature, surface density, chemical compound,
luminosity, radius, mass
o Categorizing stars
Criteria: temperature and luminosity
o HR diagram
Study Guide- Bare Bones list Physics Comprehensive Exam 2014
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For main sequence: mass is most important attribute
o Stellar remnants= compact stars at the endpoint of stellar evolution
o Heavy elements
Light elements= formed by Big Bang
Big Bang= high temperature
Heavy elements originate through supernovas
o Early universe
Hot and energetic= no particles
Today’s individual forces were unified
o Big Bang
Early development of the universe
Extremely hot and dense= expanded and cooled
Cooling= energy= subatomic particles
1st elements: Helium (He), Hydrogen (H), Lithium (Li)
Gravity pulled the above elements together to form stars.
