JEE Main & Advanced JEE Main Paper (Held on 10-4-2019 Morning)

  • question_answer A current of 5 A passes through a copper conductor (resistivity\[=1.7\times {{10}^{-8}}\Omega m\]) of radius of cross-section 5 mm. Find the mobility of the charges if their drift velocity is \[=1.1\times {{10}^{-3}}m/s.\] [JEE Main 10-4-2019 Morning]

    A) \[1.3\text{ }{{m}^{2}}/Vs\]            

    B) \[1.5\text{ }{{m}^{2}}/Vs\]

    C) \[1.8\text{ }{{m}^{2}}/Vs\]            

    D) \[1.0\text{ }{{m}^{2}}/Vs\]

    Correct Answer: D

    Solution :

    \[\mu =\frac{{{V}_{d}}}{E}\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,E=\rho J\]             \[=\frac{1.1\times {{10}^{-3}}}{1.7\times {{10}^{-8}}\times \frac{5}{\pi \times 25\times {{10}^{-6}}}}\]             \[=\frac{1.1\times {{10}^{-3}}\times \pi \times 25\times {{10}^{-6}}}{1.7\times {{10}^{-8}}\times 5}\approx 1.01{{m}^{2}}/Vs\]

You need to login to perform this action.
You will be redirected in 3 sec spinner