CEE Kerala Engineering CEE Kerala Engineering Solved Paper-2005

  • question_answer
    A straight conductor of length I carrying a current 7, is bent in the form of a semicircle. The magnetic field (in tesla) at the centre of the semicircle is:

    A)  \[\frac{{{\pi }^{2}}I}{l}\times {{10}^{-7}}\]           

    B)         \[\frac{\pi I}{l}\times {{10}^{-7}}\]

    C)  \[\frac{\pi I}{{{l}^{2}}}\times {{10}^{-7}}\]           

    D)         \[\frac{\pi {{I}^{2}}}{l}\times {{10}^{-7}}\]

    E)  \[\frac{\pi {{I}^{2}}}{{{l}^{2}}}\times {{10}^{-7}}\]

    Correct Answer: A

    Solution :

    Radius, \[r=\frac{l}{\pi }\] Magnetic field at the centre, \[B=\frac{{{\mu }_{0}}I}{4r}\]                 \[=\frac{4\pi \times {{10}^{-7}}\times I}{4\times \frac{l}{\pi }}\]                 \[=\frac{{{\pi }^{2}}I\times {{10}^{-7}}}{l}\]


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