Resistivity, Physics

Assignment Help:

RESISTIVITY:

Resistance may be defined as that property of a substance which opposes (or restricts) the flow of current (or electrons) through it. The practical as well as MKS (or SI) unit of ohm (O). 1 ohm is defined as that resistance between two points of a conductor which produces a current of one ampere. When a potential difference of 1 volt is applied to it.

If I is the current flowing through a conductor of resistance R across which a potential difference V is applied then according to ohm's law.

                                                                                      I=V/R

Where V is in volts, R is in the ohms and I is in amperes.

Resistance of a material is:

(a)          Directly proportional to its length, l R α l

(b)         Inversely proportional to its area of cross section a, Rα1/a

Combining above two facts me have R α l/a

   Or       R=ρl/A

Where ρ(rho) is a constant depending upon the nature of the material and is known as the specific resistance or resistivity of the material. Putting l=1 and a=1 expression we have R=ρ. Hence resistance of a material of unit length having unit cross-sectional area is defined as the resistivity.


Related Discussions:- Resistivity

How to make wedge, The wedge Make a wedge from a piece of wood and dri...

The wedge Make a wedge from a piece of wood and drive it inside a table leg or some other heavy object. View that the wedge is a double inclined plane

What is the centre point of gravity?, An imaginary point in a body of matte...

An imaginary point in a body of matter where, for convenience in certain calculations, the total weight of the body may be thought to be at that point.It is a point where the gravi

MOSFET, How do we experimentally know that MOSEFT device is working?

How do we experimentally know that MOSEFT device is working?

Advantages of d.c. transmission of power, Advantages of D.C. transmission o...

Advantages of D.C. transmission of power  1. It needs only two conductors as compared to three for a.c. transmission. 2. There is not an inductance, capacitance, phase displ

Boltzmann classical statistics, It describes the behaviour of a collection ...

It describes the behaviour of a collection of a particle N(E) with gives energy through N(E)α exp(-E/KT) where K is Boltzmann constant. It can be explained as a collection of

Le chateliers principle, Le Chatelier's principle (H. Le Chatelier; 1888) ...

Le Chatelier's principle (H. Le Chatelier; 1888) If a system is in equilibrium, then any change imposed onto the system tends to shift the equilibrium to decrease the effect of

Composition of simple harmonic motion, eqution of two perpendicular of somp...

eqution of two perpendicular of somple harmonic otion of same period

#LCR CIRCUIT IN PYTHON PROGRAMMING, Ask question #HOW CAN WE EXPRESS A LCR ...

Ask question #HOW CAN WE EXPRESS A LCR CIRCUIT IN PYTHON PROGRAMMING LANGUAGE#

What are the majority carriers in p-type semiconductor, In p-type semicondu...

In p-type semiconductor the majority carriers are (A) Holes. (B) Positive ions. (c) Electrons. (D) Negative ions. Ans: In p-type semiconductor the majori

Scientific report, How to set out a scientific report and include a collect...

How to set out a scientific report and include a collection and analysis of data to support my claims/findings. I am making a model and videoing it, i am wondering how to do a scie

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd