Electricity Flashcards
What does increasing the diameter of a wire do to its resistance?
It would reduce the resistance.
Gauge is the measure for wire thickness. The lower the gauge the thicker the wire. Low gauge wire has less resistance.
What three things affect a materials resistance?
Thickness, Length, Temperature, (Composition)
Resistance is a materials ability to conduct electrons
If the current of a device is 2 amps and its resistance is 10 ohms what is the voltage of the device?
20v
(2 amps)(10 ohms)=20v
What type of signal is sent by rapidly changing current between two set positions?
Digital Signals
As opposed to analog signals that are sent by smoothly changing the current through a multitude of positions.
What two things determine the strength of an electric field?
The distance from the charge.
The amount of the charge that produced the field.
What is the unit for electrical power?
Watt
A material that has electrons that are tightly bound to its atoms is generally an…?
Insulator
Tightly bound electrons do not flow easily.
A power cord is made up of a copper wire surrounded by a rubber coating. Explain why these two material were chosen to make a power cord.
The copper is a conductor which allows electrons to flow through.
The rubber is an insulator which keeps electrons from flowing outside of the wire.
What is the purpose of a circuit breaker?
To open a circuit when the wattage flowing through the circuit gets too high. This prevents damaging devices that are plugged in to the circuit.
What is the purpose of a ground fault circuit interrupter? (GFCI outlet)
It shuts off a circuit in case of a short circuit.
GFCI outlets should be used anyplace where water may get into an outlet.
The type of current that is supplied through wall outlets in the U.S. is…?
Alternating current.
The direction of the current cycles 60 times per second (hz) in the U.S.
Ever wonder why the plugs are different in Europe?
How many paths can electricity follow in a series circuit?
One
As opposed to a parallel circuit which has multiple paths.
What is maintained across the terminals of a battery? (2 answers)
A voltage drop
A potential difference
What type of current is produced by a battery?
Direct Current
What information do you need to know to calculate the power consumption of an appliance? What do you do with this information?
You need to know the amps and the voltage.
Multiply the amps times the volts.
The test question is similar but different.
If a neutral metal comb is held near an object with a negative charge it will become charged by…
Induction
The electrons move from high concentration to low concentration.
What happens when two objects of opposite charge are brought near each other.
They attract.
They will also exchange charges to become more neutral.
Information that is sent in codes and patterns that are embedded in a controlled flow of electrons are…
electronic signals
Electronic signals can be in analog or digital format.
What charge does an object take on when it gains electrons?
Negative
The difference in electrical potential energy between two places in an electric field is called the…
Potential difference
Walking across a carpet is an example of charge being transferred by…
Contact
Why are most of the circuits in your house set up in parallel circuits as opposed to series circuits?
If the circuits in your house were set up in series turning off one device would turn off all of your devices.
Game cartridges (think NES) used thin silicon chips that contained many solid state components to store game information. What are these called.
Integrated circuit.
