CET Karnataka Medical CET - Karnataka Medical Solved Paper-2014

  • question_answer
    A series LCR circuit contains inductance 5 mH, capacitance \[2\mu F\] and resistance \[10\Omega \]. If a frequency A.C. source is varied, what is the frequency at which maximum power is dissipated?

    A)  \[\frac{2}{\pi }\times {{10}^{5}}Hz\]

    B)  \[\frac{{{10}^{5}}}{\pi }Hz\]

    C)  \[\frac{5}{\pi }\times {{10}^{3}}Hz\]

    D)  \[\frac{{{10}^{-5}}}{\pi }Hz\]

    Correct Answer: C

    Solution :

    : Maximum power is dissipated at resonant frequency. Resonant frequency, \[{{\upsilon }_{r}}=\frac{1}{2\pi \sqrt{LC}}\] Here,  \[L=5mH=5\times {{10}^{-3}}H\] \[C=2\mu F=2\times {{10}^{-6}}F\] \[\therefore \]   \[{{\upsilon }_{r}}=\frac{1}{2\pi \sqrt{5\times {{10}^{-3}}\times 2\times {{10}^{-6}}}}=\frac{1}{2\pi \sqrt{{{10}^{-8}}}}\] \[=\frac{{{10}^{4}}}{2\pi }=\frac{5}{\pi }\times {{10}^{3}}Hz\]


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