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

Difference between the atomic theory and the kinetic theory, What is the di...

What is the difference between the Atomic Theory and the Kinetic Theory? Atomic theory is all about structure of an atom, i.e., its composition. Like an atom in general is made

Manufacturing process of printed circuit boards, The copper clad laminate m...

The copper clad laminate manufacturing process is formed in heated press which has highly polished stainless steel press plates. The manufacturing process starts by placing a sheet

Write any three findings of binding energy curve, Q. Write any three findin...

Q. Write any three findings of binding energy curve. (i) The binding energy per nucleon arrive at a maximum of 8.8 MeV at A = 56 corresponding to the iron nucleus (26Fe56). Th

Calculate the transmit power required from the satellite, 1.  There are 40 ...

1.  There are 40 such microwave hops in tandem.  What is the end-to-end C/N of the link? 2.  Assume now that these 40 hops are replaced by a single satellite hop as shown below.

What are solar cells, Solar Cells: The solar cells that we see on calculat...

Solar Cells: The solar cells that we see on calculators and satellites are photovoltaic cells or modules (modules are easily a group of cells electrically  connected and packaged

Paper capacitors, In this type of capacitors the dielectric consists of one...

In this type of capacitors the dielectric consists of one or more layer of extremely thin craft paper which looks very much like cigarette paper. The metal plates consist of alumin

Simple harmonic motion, what are characteristics of simple harmonic motion

what are characteristics of simple harmonic motion

Pv diagram, is always del U o in cyclic process

is always del U o in cyclic process

Inertia with a stone, Inertia with a stone You will require a stone wei...

Inertia with a stone You will require a stone weighing about 1 kg for this experiment. Wrap a length of heavy string about the stone. Now, on opposite sides of the stone, join

Buoyancy, Why do dead bodies float in water ?

Why do dead bodies float in water ?

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