Resistivity formula

What is the formula of resistance?

The formula for resistance (R) is given by Ohm’s law, which states that resistance is equal to the voltage (V) across a conductor divided by the current (I) flowing through it

R= V/I

where:

  • R is the resistance in ohms (Ω),
  • V is the voltage in volts (V),
  • I is the current in amperes (A).

What is SI unit of resistivity?

The SI unit of resistivity is the ohm-meter (Ω⋅m).

​What is resistivity in Ohm’s law?

In Ohm’s law, resistivity (ρ) represents the intrinsic resistance of a material, influencing the overall resistance (R) based on its dimensions and conductivity.

What is the full form SI unit?

The full form of the SI unit is “Système International d’Unités,” which is French for “International System of Units.”

What is unit of conductivity?

The unit of conductivity is siemens per meter (S/m).

What is Watt’s law?

Watt’s Law is a principle in electrical engineering that relates power (P), voltage (V), and current (I) in an electrical circuit.

Mathematically, it is expressed as:

P=V×I

Where:

P is the power in watts (W),

V is the voltage in volts (V),

I is the current in amperes (A).



Resistivity Formula

When a potential difference is applied across an object (conductor), the electrons start moving, which produces a current in the object. During this movement of electrons, they collide with other electrons too, which causes some opposition to the flow of electrons, this phenomenon of opposing the flow of electrons is known as Resistance(R). Its SI unit is the ohm(Ω)

Table of Content

  • Factors affecting the resistance
  • Resistivity Formula
  • Derivation of resistivity
  • SI unit of resistivity                 
  • Factors affecting the resistivity
  • Sample problems

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The resistivity of a conductor is directly proportional to its resistance [ρ ∝ R]. The resistivity of a conductor is directly proportional to its uniform cross-sectional area. [ρ ∝ A] The resistivity of a conductor is inversely proportional to its length. [ρ ∝ 1/l] Resistivity also depends upon the nature of the material and temperature as well....

Sample problems

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