Basic electricity Flashcards
(24 cards)
What constitutes a capacitor
Two conductors separated by an insulator
What is the purpose of a capacitor
It stores electrical energy in electrostatic fields
Does a capacitor in AC circuit cause the current to lead or like the voltage
It causes the current to lead the voltage
What is the basic unit of capacitance
The farad
Why should a electrolytic capacitor not be used in an AC circuits
They are polarized. An electrolytic capacitor will pass current of one polarity, but will block currents of the opposite polarity.
What is meant by Inductance
The ability to store electrical energy in electromagnetic fields
What is the basic unit of inductance
The Henry
What is an example of an and inductor used in a magneto
The coil
Does an inductour in an AC circuit cause the current to lead or lag the voltage
It causes the current to lag behind the voltage
How can you find the polarity of an electromagnet
Hold the electromagnetic in your left hand with your fingers in circling the coil in the direction electrons flow( from negative to positive ). Your thumb will point to the north pole of the electromagnet
What is meant by impedance
The total opposition to the floor alternating current. It is the vector sum of resistance, capacitive reactance, and inductive reactance.
And what unit is in impedance measured in
In ohms.
What are the five sources of electrical energy
Magnetism, chemical energy, light, heat, and pressure.
What is the basic unit of power in the DC circuit?
The watt
What is meant by a megawatt
100,000 Watts.
What is the formula for power in a DC circuit
Power=(E)(I)
What is the relationship between mechanical and electrical power
1 Horse Power = 746 Watts
What is meant by true power in an AC circuit
The product of the circuit voltage and the current that is in phase with this voltage.
And what unit is true power expressed
In Watts
What is meant by a parent power in an
AC circuit
The product of the circuit voltage and the circuit current
In what units is apparent power expressed
In volts – amps
What is meant by reactive power in an AC circuit
The power consumed in the inductive and capacitive reactants is in an AC circuit. Reactive power is also called Wattless power.
And what units is reactive power expressed
In vault – amps reactive, (VAR), or kilowatts – amps reactive(KVAR)
What is meant by power factor in an AC circuit
The ratio of true power to apparent power. It is also the ratio of circuit resistance to circuit impedance,
