CMC Medical CMC-Medical VELLORE Solved Paper-2009

  • question_answer
    A sound absorber attenuates the sound level by 20 dB. The intensity decreases by a factor of

    A)  1000                                     

    B)  10000

    C)  10                                         

    D)  100

    Correct Answer: D

    Solution :

                     Let intensity of sound be \[I\] and \[I\] Loudness of sound initially \[{{\beta }_{1}}=10\,\log \left( \frac{I}{{{I}_{0}}} \right)\] Later,    \[{{\beta }_{2}}=10\,\log \left( \frac{I}{{{I}_{0}}} \right)\] Given,   \[{{\beta }_{2}}-{{\beta }_{1}}=20\] \[\therefore \]  \[20=10\,\log \left( \frac{I}{I} \right)\] \[\therefore \]  \[I=100I\]


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