WHAT IS CONDUCTANCE -
DEFINITION OF CONDUCTANCE -
"Conductance is nothing but it is the reciprocal of resistance."
OR
Conductance is the degree to which an object conducts electricity and can be calculated as the ratio of the current which flows to the potential difference (voltage) present across the conductor. This is the reciprocal of the resistance, and is measured in siemens or mhos.
Conductance(G) = 1 / R
and by putting the value of R we get-
OR
σ - Conductivity of material(Sigma)
G - Conductance of conductor material
ρ - Resistivity of material or specific resistance
L - Length of the conductor
A - Area of cross-section of conductor
UNIT OF CONDUCTANCE- mho or simens
IMPORTANT POINTS-
➤ Conductance of any material is the inverse of resistance.
➤ A material or conductor having low resistance that means it has a high conductance value.
➤ Whereas resistance of a conductor measures the opposition which it offers to the flow of current, the conductance measures the inducement which it allow to flow of electrons. .
➤ Conductance of a material is inversely proportional to the resistance so at a constant voltage (DC) and resistance the current flowing in any conductor is also constant. if we change the conductance to half then the current flow through the conductor also reduced to half . and similarly, if G reduced to 1/5 th then current also reduced to 1/5 th of its original value and so on.
➤ one of the most important point you should remember that it (laws of conductance) holds good in case of direct current and in some low frequency ac supply also. But it can't applicable to high frequency ac . you think why?
Ok.. In high frequency ac supply, if there are some energy storing device like capacitor and inductor are connected they store and release energy in every half cycle of the supply and inductive reactance also become high in higher frequency so they affected the current flow and hence laws of conductance and laws of resistance also.
CONDUCTIVITY-
DEFINITION OF CONDUCTIVITY-
"Conductivity is nothing but it is the reciprocal of resistivity."
OR
The electrical conductivity can be defined as the conductivity offered by a cubic meter of a substance and it is the inverse of resistivity as stated above.
OR
The electrical conductivity can be defined as the conductivity offered by a cubic meter of a substance and it is the inverse of resistivity as stated above.
Mathematically,
Conductivity(σ) = 1/ρ
Where,
σ - Conductivity of material(Sigma)
ρ - Resistivity of material or specific resistance