JEE Main & Advanced Physics Alternating Current / प्रत्यावर्ती धारा Question Bank Graphical Questions

  • question_answer
    Which one of the following curves represents the variation of impedance (Z) with frequency f in series LCR circuit

    A)                                  

    B)                          

    C)                                  

    D)                          

    Correct Answer: C

    Solution :

                       \[Z=\sqrt{{{R}^{2}}+{{\left( 2\pi fL-\frac{1}{2\pi fC} \right)}^{2}}}\] From above equation at f = 0 \[\Rightarrow z=\infty \] When \[f=\frac{1}{2\pi \sqrt{LC}}\] (resonant frequency) \[\Rightarrow Z=R\] For \[f>\frac{1}{2\pi \sqrt{LC}}\Rightarrow \]Z starts increasing. i.e., for frequency 0 ? fr, Z decreases and for fr to ¥, Z increases. This is justified by graph c.


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