Electricity Flashcards
Definitions from the N5 Electricity sub-unit
What is meant by a “Electrical conductor”?
A material that lets current flow easily through it.
What is meant by an “Electrical insulator”?
A material that does not let current flow easily through it.
What is meant by “Voltage”?
The amount of energy supplied to each coulomb of charge passing through the cell.
What is meant by “Electrical current”?
The amount of charge flowing past a point in one second.
What is meant by “Direct current”?
Electron flow in one direction from negative to positive.
What is meant by “Alternating current”?
The direction of electron flow changes back and forth many times a second.
What is the value of Mains voltage in the U.K.?
230 V
What is the frequency of Mains electricity in the U.K.?
50 Hz
What is the function of a Cell or Battery in an electrical circuit?
To provide electrical energy to the circuit.
What is the function of a Bulb or Lamp in an electrical circuit?
To convert electrical energy into light energy.
What is the function of a Motor in an electrical circuit?
To convert electrical energy into kinetic energy.
What is the function of an L.E.D. in an electrical circuit?
To convert electrical energy into light energy.
What does L.E.D. stand for?
Light Emitting Diode
What does L.D.R. stand for?
Light Dependant Resistor
What environmental factor affects an L.D.R.?
Light
What environmental factor affects a Thermistor?
Temperature
What does an Ammeter measure?
Electrical Current
What does a Voltmeter measure?
Voltage
What does an Ohmmeter measure?
Resistance
What is the function of a capacitor in an electrical circuit?
A device for storing electrical charge.
What is the function of a Transistor in an electrical circuit?
Voltage dependant switch
What is meant by a “Series” circuit?
Circuit with one path for the current to flow through.
What is meant by a “Parallel” circuit?
Circuit with two or more branching paths for the current to flow through.
What is meant by “Power”?
The energy used / transferred every second.
What is the rule for series voltage?
In a series circuit, the voltage across each component adds to the supply voltage.
What is the rule for series current?
In a series circuit, the current is the same at all points.
What is the rule for parallel voltage?
In a parallel circuit, the voltage across each branch is equal to the supply voltage.
What is the rule for parallel current?
In a parallel circuit, the current through each branch adds to the supply current.
What is the purpose of a resistor in series with an LED?
To protect the LED from too large a current.
