A) \[2.4\times {{10}^{-6}}\Omega \,m\]
B) \[1.2\times {{10}^{-6}}\Omega \,m\]
C) \[1.2\times {{10}^{-8}}\Omega \,m\]
D) \[2.4\times {{10}^{-8}}\Omega \,m\]
Correct Answer: D
Solution :
The resistance R of a particular conductor is related to the resistivity p of its material by \[R=\frac{\rho l}{A}\] or p = resistivity \[=\frac{RA}{l}\] Given, \[R=0.0072\,\,\Omega \], \[A=2\,mm\times 2mm=4\times {{10}^{-6}}{{m}^{2}},l=12\,mm\] \[\therefore \] \[\rho =\frac{0.072\times 4\times {{10}^{-6}}}{12}\] \[0.0024\times {{10}^{-6}}\Omega \,m\] \[=2.4\times {{10}^{-8}}\Omega \,m\]You need to login to perform this action.
You will be redirected in
3 sec