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

Definition of collision, COLLISION:  "When two or more bodies come cl...

COLLISION:  "When two or more bodies come close to each other, so that there is some part of interaction among them, with or without the presence of external force, we say tha

Matlab, contact ball whit wall box

contact ball whit wall box

Newtons laws the motorcyclist, Newtons laws The Motorcyclist As per to ...

Newtons laws The Motorcyclist As per to Newton's first law an object which is in motion continues in motion along with the similar speed and within the similar direction unless

Explain the term magnetic declination, Explain the terms (i) magnetic decli...

Explain the terms (i) magnetic declination and (ii) angle of dip at a given place.

Name the losses occurring in a transformer, The losses occurring in a trans...

The losses occurring in a transformer are:- I) iron loss II) copper loss

Electric field and the associated magnetic field, What the angles among the...

What the angles among the direction are of travel of light the electric field and the associated magnetic field? Answer: The magnetic field created by a changing electric

Rayleigh''s criterion of just resolution of two spectral line, Q.  Explain...

Q.  Explain Rayleigh's criterion of just resolution of two spectral lines of equal intensities giving suitable intensity distribution carves. Show how the resolving power of a pla

What is the static electricity, What is the Static Electricity Have yo...

What is the Static Electricity Have you ever had your hair stand on end after rubbing a balloon on your hair before a birthday party? You have probably experienced static e

Impulse, if a 5-kg object experience a 10-n force for a 0.10-second, then w...

if a 5-kg object experience a 10-n force for a 0.10-second, then what is momentum change of the object

Newton law, what is newton first law of motion

what is newton first law of motion

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