2. Questions Bank
  3. 9th Class
  4. Science
  5. Sound

9th Class Science Sound Question Bank Sound Summative Objective Problems

  • question_answer
    A sound wave travelling in air has wavelength of\[1.6\times {{10}^{-2}}m.\]If the velocity of sound is 320m/s, calculate the frequency of sound.

    A)  10,000 Hz           

    B)  20,000 Hz

    C)  15,000 Hz                           

    D)  25,000 Hz

    Correct Answer: B

    Solution :

      \[\lambda =1.6\times {{10}^{-2}}m\] \[v=320\text{ }m/s\] \[f=?\] We know, \[V=f\lambda \]                                 \[f=\frac{v}{\lambda }\]                                 \[=\frac{320}{1.6\times {{10}^{-2}}}=20,000Hz\]


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