JEE Main & Advanced Physics Wave Mechanics Question Bank Musical Sound

  • question_answer
    The intensity level due to two waves of the same frequency in a given medium are 1 bel and 5 bel. Then the ratio of amplitudes is

    A)            1 : 4                                          

    B)            1 : 2

    C)            1 : 104                                      

    D)            1 : 102

    Correct Answer: D

    Solution :

                       By using  \[L={{\log }_{10}}\frac{I}{{{I}_{0}}}\] \[{{L}_{2}}-{{L}_{1}}={{\log }_{10}}\frac{{{I}_{2}}}{{{I}_{0}}}-{{\log }_{10}}\frac{{{I}_{1}}}{{{I}_{0}}}\] \[5-1={{\log }_{10}}\frac{{{I}_{2}}}{{{I}_{1}}}\]Þ \[4={{\log }_{10}}\frac{{{I}_{2}}}{{{I}_{1}}}\]Þ \[\frac{{{I}_{2}}}{{{I}_{1}}}={{10}^{4}}\] Þ \[\frac{a_{2}^{2}}{a_{1}^{2}}={{10}^{4}}\]Þ \[\frac{{{a}_{2}}}{{{a}_{1}}}=\frac{{{10}^{2}}}{1}\]Þ \[\frac{{{a}_{1}}}{{{a}_{2}}}=\frac{1}{{{10}^{2}}}\]


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