RESISTANCE AND CONDUCTANCE

Resistance:

The property of a material which opposes the flow of current is known Resistance.
The Units of Resistance is

kilo ohm's.

Mega ohm's.

Milli ohm's.

Micro ohm's.

The device used for this purpose is known as a Resistor.
These are widely used in electric circuits.

Law of Resistance:

Resistance is directly proportional to length of the material.
Resistance is inversely proportional to area of the conductor

R=(rho)×(l/a)

Here,

rho-Resistivity or specific resistance

l-length of material

a-Area of the material.

The unit of this Resistivity are

Ohm's per meter

Ohm's per meter cube

Ohm's per centimetre

Ohm's per centimetre cube

Where,
1 ohm per meter=100 ohm's per centimetre

Conductance:

It is just a reciprocal of Resistance.
It is the property of a material which allows the flow of current.
One of the best conducting material is copper.
The units of this condutance is Mho.
It id denoted by a letter G

G=(conductivity)×(a/l)

The units of this conductivity are mho per meter.

Comments

GENERATOR

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