Electrostatics & Electrodynamics Flashcards
If electrons are removed, an atom is
positive
Addition of an electron to a neutral atom, causes the atom to be
negative
What is an atom with too many or too few electrons?
an ion
On what shell of an atom are the electrons bound most tightly?
K shell
a quanity (expressed in kilograms)
mass
shape or structure that gives it distinctive character
form
the ability to do work (expressed in joules)
energy
the branch of physics that deals with stationary or resting charges
electrostatics
process of removing or adding electrons to a body of matter
electrification
what is a neutral object that is always available to accept electric charges from an electrified object
earth
3 methods of electrification
friction
induction
contact
what is the removal of electrons from one object by rubbing it with another object
friction
when 2 objects touch, permits electrons to move from one object to another
contact
electrical fields acting on one another without contact
induction
what type of electrification do we deal with when creating xrays
induction
what are the 4 types of conductivity?
nonconductors or insulators
conductors
semiconductors
superconductors
what type of conductor has no resistance to electron flow (it must be very cold)
superconductors
what type allows free flow of electrons
conductors
what type does not allow free flow of electrons
nonconductors or insulators
the 5 laws of electrostatics
- ) like charges repel, unlike charges attract
- ) Coulomb’s law - the square of the distance
- ) Electric charges reside only on external surfaces of conductors
- ) the concentration of charges on a curved surface of a conductor is greater when the curvature is greater
- ) only negative charges can move on solid conductors
What is the unit of electric charge?
coulomb
What is the unit of electric potential?
volt
What is the unit of electrical current?
amperage
What is the unit of electrical resistance?
ohms
What is the unit of electrical power?
watt
What is the unit of electrostatic force?
newtons
What is the science of electrostatic charges in motion?
electrodynamics
What are the 3 factors in electric current?
- ) potential differences
- ) current
- ) resistance
resistance depends on what 4 things?
- ) material
- ) length - increase length, increase resistance
- ) cross-sectional area - decrease cross section, increase resistance
- ) temperature - increase temp., increase resistance
what law is the potential difference divided by the RESISTANCE?
Ohm’s law
what is the formula for the power of electric current?
power = amp x voltage
with what type of current do electrons flow in one direction?
direct
with what type of current do electrons oscillate back and forth?
alternating
Hertz is the _________
frequency
