Electricity
General term for the variety of phenomena resulting from the presence and flow of electric current
Volts
Amperes (amps)
Ohms
3 ways
... [Show More] Electricity is measured
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Volts
Measure the difference of potential between 2 points
Amperes (amps)
Measure the number of electrons that move past a specific point in 1 second
(i.e. electrical currents)
Ohms
Measure resistance, including anything that could limit the flow of electrons
Current
Electrical ___ occurs when electrons move from one place to another.
Conductors
(e.g. copper, silver, water)
A substance, body, or device that conducts electricity; allows the electrons to move freely.
Insulators
(e.g. rubber, wood)
A material of such low conductivity that does not easily allow the flow of electrical current to pass through it; discourages electrical current
Watt
This measures power, the rate at which electrical energy is consumed or transformed into another type of energy, such as light or heat
Power
The rate at which electrical energy is consumed or transformed into another type of energy, such as light or heat
Watt-hour
This is the amount of energy used in 1 hour at a rate of 1 watt.
Kilowatt-hour
The amount of energy used in 1 hour at a rate of 1,000 watts(i.e.1-kilowatt)
True
True or False
Most electricity is measured in kilowatt-hours
Wattage x Time (expressed in hours)
To find watt-hours multiply ___ by ___.
10 kilowatt-hours
How many kilowatt-hours is enough energy to run a 10,000-watt speaker system for 1 hour?
2 hours
10 kilowatt-hours is enough energy to run a 5,000-watt air conditioner for how long?
10 hours
10 kilowatt-hours is enough energy to run a 1,000-watt waffle iron for how long?
Circuit
The path of an electrical current
Open
When there is literally an open space in the circuit that prohibits current from flowing
Short
When the open space of a circuit has been closed to allow current to flow
Voltage
The difference of the pressure between 2 points in a circuit
(sometimes called voltage drop or difference of potential)
True
True or False
To see what the voltage is anywhere in a circuit, you have to compare the voltage at that point to ground
Ground
(e.g. base of a lamp, chassis of a car)
Any part of a circuit (or other object that has electricity running through it) that measures 0 volts
Voltmeter or multimeter
Measures voltage in a circuit
Voltmeter
An instrument used for measuring electrical potential difference between two points in an electric circuit (i.e. voltage)
A voltmeter has 2 leads. To measure voltage, you place one lead somewhere in the circuit and one lead at another location in the circuit. The voltmeter tells you what the voltage is between those 2 points.
How to use a voltmeter:
Cell
A storage compartment for electricity in a battery that has a specific voltage.
True
True or False
You can figure out the number of cells a battery has by dividing the voltage of the battery by the volts.
Electrical current
The flow (rate of flow) of electrons in a conductor
coulombs (C), which measure charge.
Current flow can be expressed in terms of ___.
Coulomb
The amount of electricity provided by a current of 1 ampere flowing for 1 second.
True
True or False
If 1 coulomb (about 6,241,500,000,000,000,000 electrons) flows past a specified point in 1 second, that's a flow rate of 1 ampere (amp, abbreviated A).
Ammeters
Measure the flow of current through a circuit
True
True or False
Typically current is tiny, so small that it's measured in milliamperes; 1 milliampere is one-thousandth of an ampere. [Show Less]