Electricity Flashcards
Static Electricity
The electricity that builds up on the surface of an object caused by friction.
Conductor
A material that allows electricity to pass through it (Usually metals).
Insulator
A material that doesn’t allow the flow of electricity.
Battery
Batteries and similar devices accept, store, and release electricity on demand.
Circuit
A circuit is a closed loop that electrons can travel in.
Ammeter
an instrument for measuring electric current in amperes.
Voltmeter
an instrument for measuring electric potential in volts.
Grounding
Grounding an object transfers electrons between the object and the earths surface, making the object neutral.
Discharge
Electrical discharge occurs when electrical charges are transferred very quickly. (Sparks)
Load
An electrical load is simply any component of a circuit that consumes power or energy.
Electron
In the wires of electric circuits, an electron is the actual charge carrier. They have negative charges.
Electron affinity
A material’s ability to hold on to electrons
Friction
Two objects rubbing together cause friction
Induction
The movement of electrons within a substance caused by the nearby charged object, without direct contact between the substance and object.
Charging by contact
Occurs when electrons transfer from the charged object to the neutral object that it touches.
Law of Attraction and Repulsion
Like charges repel and Opposites attract
Electroscope
A device that detects static electricity by using thin metal
Electrostatics
The study of static electric charges
What are the necessary parts of a circuit
A energy source: battery
Conductor: Wires
Load: lightbulb
And switch (optional)
Open Circuit
An electrical path having a break in; electrons don’t flow through
Closed circuit
An unbroken path through which electrons are moving
What is Electric current measured in?
Amperes
What is resistance
The measure of how easily current can flow through a material (measured in ohms)
Series Circuit
A circuit with only 1 path
Parallel circuit
A circuit with many paths
Resistors
Restrict the flow of electrons
Potential Difference in Series Circuit
Shared between the loads
Potential Difference in Parallel Circuits
Work done per unit charge
Current in series circuit
The same throughout
Current in Parallel Circuit
Shared between the paths
Resistors in series circuits
Adding more loads reduces the current
Resistors in Parallel Circuits
Adding more loads allows more current to flow through
Potential Energy
The energy stored in an object
Batteries flow in circuits
Electrons flow from the negative end to the positive end
Potential Difference
The difference in electrical potential energy between two points
The SI unit for measuring potential difference is
VOLT
Electric current
The measure of the amount of electric charge that passes by a point in an electrical circuit each second.
Two types of electric current
DC: Direct current
AC: Alternating Current
Direct current
Current that flows in one direction. The flow of a current from a bettery is DC
Alternating current
Flows back and forth at regular intervals called cycles
An Ampere
The measure of the amount of charge moving past a point in the circuit every second
More resistance =
more energy gains
Electrons entering the resistor is where the
Potential energy is greater
More loads in parallel circuit=
will decrease the total resistance
Total voltage in series circuit is
The sum of the voltages across each load
Total current in a parallel circuit is
Equal to the sum of the individual branch currents. Each pathway shares the amount of current for the source.
The voltage in a parallel circuit is
the same throughout.
Ohms Law
Describes the relationship between Voltage, Resistance and current. V=LxR
Current (I) =
V/R
Resistance =
V/I
If Current increases
Voltage must also (Vice Versa)
Temp affects
Resistance
Temp increases
Resistance increases, and conductivity decreases
Temp decreases
Resistance decreases, and conductivity increases
Short Circuit
An accidental low resistance connection between two points in a circuit. Current can flow easier through wires than lightbulbs, which creates a dangerous short circuit.
Two devices in the home that act as defense to short circuits
Fuses and Circuit breakers
What’s a fuse?
A fuse is a safety device in an electrical circuit that has a metallic conductor with a low melting point compared to the circuit’s wires. If the current gets too high, the metal melts, thus closing the circuit.
Circuit Breaker
It does the same job as a fuse except the wire doesn’t melt, it heats up and bends, which triggers a spring that turns off the flow of electricity. Unlike a fuse, this doesn’t have to be replaced, it cools down and resets.
Three Prong Electrical Plug
This is another safety feature. The third prong connects the device to the ground wire of the building in case of a short circuit.
Ground Fault Circuit Interrupter (GFCI)
Detects a current in change and opens, stopping the flow. If smth gets wet while handling it and some current starts to flow through the water, the GFCI opens the circuit so that there is less injury to you.
