Electricity definitions Flashcards
1
Q
What is charge?
A
Presence of absence of electrons, measured in Coloumb
1c = 6.24 x 10 to the power of 18 electrons
2
Q
What is current?
A
Flow of electrons in amps = 1 coloumb per second
3
Q
What is voltage?
A
The driving force of current
4
Q
What is resistance?
A
Opposition to current flow (in DC)
5
Q
What is reactance?
A
Opposition to AC current flow
6
Q
What is impedance?
A
Total resistance to flow e.g. resistance, reactance and capacitance etc.
7
Q
What is capacitance?
A
Ability to store charge
8
Q
What is inductance?
A
Ability to generate resistive EMF to oppose flow
Rapidly changing current produces EMF
1 H = 1A generating 1Wb
9
Q
What is a transformer?
A
Transfers energy e.g. step up or down
10
Q
Why is a diode?
A
Also called a rectifier.
1 way valve for current
