Electricity Test
conductor
1. a material through which charge can flow easily 2. they transfer electric charges well 3. the electrons are bound loosely and move throughout the material to form electric current Examples: wire, spatula, spoon, and a pot
insulator
1. a material through which charges cannot flow easily 2. they do not transfer electric charge well 3. the electrons are bound tightly and do not move easily 4. they are used to stop the flow of electric charges Examples: rubber, sand, glass, and plastic
Ohm
An ___ measures resistance.
increase, greater
An _____ in voltage causes a ____ flow of electric current.
energy source
Another name for voltage source is ___.
Yes (Fluorescent light bulbs)
Can gas be a conductor?
difference in electrical potential energy
Charges in an electric current flow because of a ____.
conducting wires
Circuits are connected by ___. These wires allow charges to flow from the energy source to the device that runs on electric current and back to the energy source.
source
Circuits have a ____ of electrical energy. It allows the charges to move around the circuit. (examples: batteries, generators, power plants)
low
Conductors have ____ resistance.
path, continuously
Electric current requires a specific ____ to follow and it must flow ___ from one place to another in a loop.
conductor, pulled, pushed
Electrons are inside the _____. When we flip the switch, electrons on one end of the wire are ___ while those at the other end are ____.
it would decrease
If a 4th bulb were added to three existing bulbs in a parallel circuit, what would happen to the resistance in the circuit?
it would be increase
If a 4th bulb were added to three existing bulbs in a series circuit, what would happen to the resistance in the circuit?
least resistance
If an electric charge can flow through either of two paths, more charges will flow through the path with ____.
it must keep flowing continuously
If an electric circuit is broken, electric current cannot exist because ___.
they still work
In a parallel circuit, if one light bulb burns out, what happens to the others?
they stop working
In a series circuit, if one light bulb burns out, what happens to the others?
more
Long wires have ____ resistance than short wires.
amps, flowing, second
Number of ___ equals the amount of charge ____ past a given point each ___.
electrical energy, energy
Resistors transform ____ into another form of ___.
greater, less
The ____ the resistance, the ___ current there is for a given voltage.
rate of electric current
The amount of charge that passes through a wire in a unit of time
less
The greater the resistance, the ___ current there is for a given voltage.
thickeness, length, what it is made of
The resistance of a wire depends on the ___ and ___ of the wire, as well as ____.
120 V
The voltage in most household circuits is ____.
more
Thin wires have ___ resistance than wide wires.
1. material from which it is made 2. length of material 3. diameter of material 4. temperature of material
What are four factors that determine the resistance of an object (usually a wire)?
1. Circuits have devices that are run by electrical energy 2. Circuits have a source of electricaly energy 3. Circuits are connected by conducting wires
What are the three features of circuits?
resistors, energy source, wires
What are the three parts of all electric circuits?
Electric's current flow is continuous. Static electricity's isn't.
What is the difference between statis electricity and electric current?
There is an insulator around the wire.
Why aren't we shocked when we turn on a light switch?
electrons
___ carry a negative electric charges. As they flow they form electric current.
solenoid
a coil of wire with a current
battery
a combination of two or more electrochemical cells in a series
electric circuit
a complete, unbroken path through which electric charges can flow
voltage source
a device that creates a potential difference in an electric circuit (battery, power plant)
electrochemical cell
a device that transforms chemical energy into electrical energy (example: battery)
ammeter
a device used to measure current
voltmeter
a device used to measure voltage (potential difference)
chemical reaction
a process in which substances change into a new substance with different properties
electrolyte
a substance that conducts electric current (water)
Luigi Galvani
an Italian physician who was studying the anatomy of a frog who accidentally developed the battery.
Alessandro Volta
an Italian scientist who built the first electric battery by layering zinc, paper soaked in salt water, and silver.
wet cell
an electrochemical cell in which the electrolyte is a liquid (example: automobile batteries)
dry cell
an electrochemical cell in which the electrolyte is a paste (example: flashlight)
circ
around
duct
bring, take; to lead, draw
sect
cut
resistors
devices that are run by electrical energy (examples: light bulb, TV, fridge, toaster)
tele
far, far away
psych
mind
er
one who
demo
people
voltage
potential difference—the difference in electrical potential energy between two places in a circuit. It causes current to flow through an electric circuit.
ity
state of
Ohm's Law
states that the resistance is equal to the voltage divided by the current Voltage Resistance = ---------------- Current Voltage = Resistance x Current
A
symbol for amps = current
∩
symbol for ohms = resistance
V
symbol for volts = voltage
electric current
the continuous flow of electric charges through a material (conductor). This is caused by a difference in electrical potential energy.
potential difference
the difference in electrical potential between two places
parallel circuit
the different parts of the circuit are on separate branches; there are several paths for the current to take
potential energy
the energy an object has as a result of its position
resistance
the measure of how difficult it is for charge to flow through a material
terminal
the part of an electrode above the surface of the electrolyte; used to connect the cell to a circuit. There are two of them.
electrical potential
the potential energy per unit of electric charge
volt
the unit of measure of voltage
series circuit
there is only one path for the current to take; all the parts of the electric circuit are connected one after another along one path
electrodes
two different metals that are immersed in a substance called electrolyte (silver, zinc)
ampere (amp)
unit for the rate of current
intra
within, inside of