InterviewSolution
Saved Bookmarks
InterviewSolution
| 1. |
The resistively of a condu is given by the expression : `p = RA//l` where `R` is the independent of dimension of conductor it deped on the meters of material and temperature of condections Read the show paragraph and answer the following question: (i) For whichmeterial is the resistivity (i) zero (ii) infinite ? (ii) Find the resistent of a bellow cylindrical of the meterial of cylinderical pipe is `2 xx 10^(-3) Omega m` (iii) How is the knowinledge of resistance metel in over dally life ? |
|
Answer» The resistively is zero for toper conbinations like at critical temperature `4.2K` motion at critical temperature `9.2k` and the resistance is inifnite for a perfect insilner like dry wood and hard glass (i) Here`I = 1.0cm,r_(1)= 0.10m, r_(2)= 0.20 m,rho= 2xxx10^(-6)Omega m` `R=(rhol)/(pi(r_(2)^(2)-r_(1)^(2)))=((2xx10^(-8))xx1)/((22//7)[(0.2)^(2)-(0.1)^(2)])=2.1 xx10^(-7) Omega` (iii) The knowladge of respectively of difference meterial helps as in selecting satable material for differece perposs for example a in making a tranedrelasence cell magain or constant wire is used as in resistanceis very lange .The length required for a given resistance would be small b in making the heater cell inclinedd wire is used as in resistance and inclined are high c copper wire are used as connecting wires to electrical experiment of copper is very low |
|