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Flashcards in electricity Deck (11):
1

current (I):

the measure of the flow of electrons, measured in amps (A)

2

potential difference(V):

measured in volts (V)

3

resistance(R):

how difficult it is for electrons to move through a component or wire, measured in ohms (Ω)

4

power(P):

the rate at which electrical energy is supplied to a circuit, measured in watts (W) or joules per second(j/s)

5

charge(Q):

measured in coulombs (C)

6

what is a non ohmic conductor?

a non ohmic conductor is a component which does not follow ohms law so it's graph is non linear.

7

how is a filament bulb an non ohmic conductor?

a filament bulb consists of a thin metal wire and so when the temperature increases the resistivity increases. This also happens in the opposite direction.

8

features of a diode:

-diodes let through a small current until the threshold voltage is reached then it allows a lot of current to pass.
-diodes can change a A.C to a D.C
- can be used to protect sensitive circuits
-only allows current to travel one way

9

what is the link between resistivity and conductivity?

a material with low resistivity means it will allow current to flow easier, so metals with a low resistivity are good conductors.

10

how would you expect the resistance of a diode to vary as pd increases?

as pd increases then resistance will decrease, it will start high and then become lower.

11

what is meant by a non ohmic conductor?

a non ohmic conductor does not have a constant resistance.