Physics Chapter 34
standard voltage in the United States is
110-120v
current in laptops and cell phones is
DC
the current in a circuit is directly proportional to the voltage impressed across the circuit, and is inversely proportional to the resistance of the circuit
Ohm's Law
the relationship among current, voltage, and resistance
Ohm's Law
repeatedly reverses direction flow of charge
alternating current (AC)
SI unit used to measure electric current
ampere
equivalent to 1 Coulomb of charge per second
ampere
the source of electrons in a circuit is the...
conducting circuit material itself
particles within a solid conductor that carry charge throughout a circuit
conduction electrons
the damaging effects of electric shock are the result of ________ passing through the body
current
electric power formula
current X voltage
Ohm's Law mathematically
current= voltage/resistance
tiny electronic device that acts as a one-way valve to allow electron flow in only one direction
diode
flow of charge that always flows in 1 direction
direct current (DC)
the flow of electric charge
electric current
rate at which electrical energy is converted into another form such as mechanical energy, heat, or light
electric power
the resistance that a conductor offers to the flow of charge
electric resistance
when you plug a lamp in an AC outlet, what flows?
energy
T or F: the amount of charge that flows in a circuit does not depend on the voltage provided by the voltage source
false
what 2 forms of energy are produced when you turn on a light?
heat and light
what does a 60- hertz current mean
it means that the current alternates back and forth at 60 cycles per second
electric resistance is measured in units called ______
ohms
charge flows when there is a ______________________ between the ends of a conductor
potential difference
elements in a circuit that are used to regulate current
resistors
the resistance of some materials becomes zero at very low temperatures
superconductivity
charges flow _______ a circuit because of an applied voltage _______ the circuit
through, across
equivalent resistance
to calculate in series: sum of the values in parallel: half of the value of either resistor
T or F: a pulsating electric field can travel through a circuit at nearly the speed of light
true
T or F: energy is transported through connecting wires of a circuit at nearly the speed of light
true
T or F: the potential energy per coulomb of charge available to electrons moving between the terminals of a battery or generator is the voltage
true
something that provides a potential difference
voltage source
the net charge in a current- carrying wire
zero