Electric Forces and Fields, Electrical Potential Energy, Electric Current and Resistance
the unit for electric force is ____ with converts to
N, kg x m/s^2
the process of charging a conductor by bringing it near another charged object and grounding the conductor
induction
the reference point for potential difference near a point charge is often at _______-
infinity
materials in which electric charges do not move freely are called ______. examples?
insulators, glass, rubber, silk, and plastic
generators convert _______ __________ into ____ _________
mechanical energy, electrical energy
electrical energy is transferred at high potential differences and low currents to
minimize energy loss
the electric field of a point charge is an example of a ___________ field because the field strength decreases as distance from the charge increases
nonuniform
through milkan's ______ _____ experiment, he discovered that electric charge is ________
oil drop, quantized
describes two or more components in a circuit that are connected across common points or junctions, providing separate conducting paths for the current
parallel
the equivalent resistance of resistors in ______ can be calculated using a reciprocal relationship
parallel
the sum of currents in______ resistors equals the total current
parallel
the superposition principle for electric potential at a point near two or more charges states that the total electric potential at some point near several point charges is the _________ of the electric potentials resulting from each of the individual charges
algebraic sum
opposite charges
attract
an electric potential exists at some point in an electric field regardless of whether there is a ____________--
charge at that point
positive and negative charges in motion are called _____ _______, they can be both positive and negative
charge carriers
electric field strength depends on _____ and ______
charge, distance
batteries convert _____ ________ to ______ _______ _________-
chemical energy, electrical potential energy
materials in which electric charges move freely are called ______, examples? Most _____ are these.
conductors, copper, aluminum, metals
electric charge is ______ and the opposite charges are equal in _______
conserved, magnitude
resistance is _______ over a wide range of applied potential differences, known as ____ _____, formula?
constant, ohm's law, delta V = IR
both insulators and conductors can become charged by
contact
positive charge movement
conventional current
resistors can be used to control in the amount of ________ in a conductor
current
the rate of charge movement, Si unit?
current, amperes
the ______ between two objects affects the magnitude of the electric force between them
distance
the net velocity of a charge carrier moving in an electric field
drift velocity
a set of electrical components connected so that they provide one or more complete paths for the movement of charges
electric circuit
electric field lines for charges that are equal magnitudes but opposite signs display a charge configuration called
electric dipole
a region in space around a charged object in which a stationary charged object experiences an electric force because of its charge
electric field
lines that represent both the magnitude and the direction of the electric field, the number of field lines is proportional to the ______ _______ ________, Thus E is stronger where the field lines are ________ and weaker where they are _____
electric field lines, electric field strength, close, far
equation for electric field strength from a point charge is
electric field strength = Coulomb constant x (charge producing the field / (distance)^2
because two charged objects near one another may experience motion either toward or away from each other, each object exerts a force on the other object. This force is called the ______ ______ .
electric force
Coulomb's law, the equation that expresses the relationship between distance, charge, and electric force, is _____________________.
electric force = coulomb constant x (charge 1 x charge 2) / (distance)^2
the electrical potential energy associated with a charged particle divided by the charge of the particle
electric potential
the rate of conversion of electrical energy, formula?
electric power, P = I(deltaV)
potential energy associated with an object due to its position relative to a source of electric force
electrical potential energy
what is the equation for electrical potential energy in a uniform electric field
electrical potential energy = -(charge x electric field strength x displacement from the reference point in the direction of the field)
what is the formula electrical potential energy for a pair of charges
electrical potential energy = Coulomb constant x (charge 1 x charge 2 / distance)
when no net motion of charge is occurring within a conductor, the conductor is said to be in ________ _________--
electrostatic equilibrium
electric force is what type of force?
field force
what is the SI unit for electrical potential energy
joule
the unit for electrical potential energy is, the unit for electric potential and potential difference is
joule, volt
resistance depends on
length, cross-sectional area, material, and temperature
electrical potential energy is a form of _________ energy
mechanical
what did benjamin franklin do?
name the two different kinds of charges positive and negative
in electrostatic situations, the equilibrium position of a charge is the location at which the __ ______ ______ on the charge is _____.
net electric force, zero
materials that have a constant resistance over a wide range of potential differences are said to be, those that dont are said to be, one common semiconducting device that is non-ohmic is the ______, which are used in circuits to control the ______ of the current
ohmic, non ohmic, diode, direction
a surface charge can be induced on insulators by ___________, which is the realignment of charge within individual molecules producing an induced charge on the surface of an insulator. An insulator that is this has no net charge but is still able to repel or attract objects due to its realignment of charge
polarization
the rules for drawing electric field lines are that 1) the lines must begin on _____ ______ or at _______ and must terminate at ______ or at ______. 2) the number of lines drawn leaving a positive charge or approaching a negative charge is proportional to the _________ of the charge. 3) no two field lines from the same field can _____ each other
positive charges, infinity, negative charges, infinity, magnitude, cross
the change in electrical potential energy associated with a charged particle divided by the charge of the particle
potential difference
what is the formula for potential difference in a uniform electric field
potential difference = -(magnitude of the electric field x displacement)
what is the equation for potential difference between a point at infinity and a point near a point charge
potential difference = Coulomb constant x (value of the point charge / distance to the point charge)
what is the formula for potential difference between two points?
potential difference = change in electrical potential energy/ electric charge
resistors in parallel have the same _____ _________ across them
potential differences
like charges
repel
the opposition to the flow of current in a conductor
resistance
formula for resistance? SI unit for resistance?
resistance = potential difference / current, ohms
when many resistors are connected in a series, the current in each resistor is the ____
same
a uniform field is a field that has the __________________
same value and direction at all points
electric potentials are _____ quanities
scalar
third class of materials characterized by electrical properties that are somewhere between those of insulators and conductors. in their _____ state they are insulators, but addition of _______ ______ __ _________ can dramatically increase ability to conduct electric charge. Examples?
semiconductors, pure, specific atoms as impurities, germanium and silicon
describes a circuit or portion of a circuit that provides a single conducting path without junctions
series
equivalent resistance equals the total of individual resistances in a
series
what types of circuits are hazardous
short circuits
a test charge is a _____ ______ _______ and is used to determine direction of electric field
small positive charge
a material whose resistance is zero at or below some critical temperature, which varies with each material
superconductor
metals that become perfect conductors when they are at or below a certain temperature
superconductors
electric field lines are ________ to the electric field vector at any point, and the number of lines is proportional to the ______ of the field strength
tangent, magnitude
coulomb quantified electric force with a ______ _______
torsion balance
a ___ ____ _____ generator collects electric charge
van de graaff
electric field (E) is a ____ quantity
vector
the resultant force on any single charge equals the ______ ____ of the individual forces exerted on that charge by all the other individual charges that are present, this is an example of the _____- ______ ______
vector sum, principle of superposition
unit for potential difference? current? resistance? electric power?
volt, ampere, ohm, watt
when conductors are in electrostatic equilibrium, the electric field is ______ everywhere inside the conductor, any excess charge on an isolated conductor resides entirely on the conductor's ____ _____, the electric field outside a charged conductor is _______ to the conductor's surface, and on an irregularly shaped conductor, charge tends to accumulate where the radius of curvature of the surface is ______, that is, at sharp points.
zero, outer surface, perpendicular, smallest
milkan discovered the value of an electron is __________, and the value of a proton is ______, and the charge of a neutron is?
-1.60 x 10 ^ -19 C, + 1.60 x 10 ^ -19 C, 0
what is the coulomb constant and it's SI units?
8.99 x 10^9 N x m^2/ C^2
what is the mass of an electron? of a proton? neutron?
9.109 x 10 ^ -31 kg, 1.673 x 10 ^ -27 kg, 1.675 x 10 ^ -27 kg
what is the SI unit of electric charge?
Coulomb
charges move in one direction in ____ _____, and alternate in ______________
DC, AC
equation for calculating electric field strength, q0 means an object with a _____ ______ ______, the SI units for E are
E = Felectric / q0, small positive charge, N/C
the power dissipated by a resistor can be calculated with the what equation
P = (delta V)^2/R