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

Which ship gets hit ?rst, A battleship concurrently ?res two shells at enem...

A battleship concurrently ?res two shells at enemy ships along the trajectories shown. One ship (A) is close by; the other ship (B) is far away. Which ship gets hit ?rst?

What are non-polar molecules, Q. What are non-polar molecules? Give an exam...

Q. What are non-polar molecules? Give an example. i) A non-polar molecule is one in that the centre of gravity of the positive charges coincides with the centre of gravity of

Determine the fringe width in youngs double slit, The fringe width in a You...

The fringe width in a Young's double slit arrangement is 0.008cm. What could be the fringe width if the slit separation is halved and the screen slit distance is doubled?

Evaluate the direction of the current in circuit, Q. Point out the directio...

Q. Point out the direction of the current if any induced to flow in the coil by the changing magnetic field. Answer: 1. Given: declining number of magnetic field line

Research paper writing, how to write a paper when it is based on matlab pro...

how to write a paper when it is based on matlab program

Describe the type of analysis , Suppose that a colleague comes to you for h...

Suppose that a colleague comes to you for help prior to conducting an experiment with two treatments to determine the effects on the density (weight) of cornbread.  The recipe for

Wave optics, can I get ready made project for wave optic?

can I get ready made project for wave optic?

Describe positive rays, Positive rays are sometimes called as the canal wav...

Positive rays are sometimes called as the canal waves. These were found by Goldstein. If the cathode of a discharged tube has holes in it and the pressure of the gas is around 10-3

Atoms And Nuclei, Prove that the various stationary orbit are not equally s...

Prove that the various stationary orbit are not equally spaced?

DELAY LINE, WHY WE USE DELAY LINE IN CRO WHAT HAPPENS IF WE NOT USE IT?

WHY WE USE DELAY LINE IN CRO WHAT HAPPENS IF WE NOT USE IT?

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