1.11 Resistance, Resistivity Flashcards
1
Q
Ohms law
A
The current through a metallic conductor is directly proportional to the applied pd, provided the temperature is constant
2
Q
Resistance question
A
R=V/I
3
Q
Joules law equations
A
P=I^2.R
P=V^2/R
4
Q
Resistors in series
A
Rt=R1+R2+R3…
5
Q
Resistors In parallel
A
1/Rt=1/R1+1/R2+1/R3…
Or when it is just two
Rt= R1xR2/R1+R2
6
Q
Resistivity equation
A
q=RA/L
7
Q
EMF equation
A
E=I(R+r)
8
Q
Internal resistance equation
A
E=Ir+V
9
Q
Superconductor definition
A
A material which loses all of its electrical resistivity to become a perfect conductor when below its critical temperature
10
Q
Resistivity definition
A
The resistance of 1m of material of cross sectional area 1m^2
11
Q
Lost volts definition
A
‘The energy dissipated per unit charge within a cell due to the interns, resistance’
