Available Answers

1. 1.

   Choose the most appropriate answer.

   1. The sound that can be heard by a human ear is called
      1. soft sound.
      2. loud sound.
      3. audible sound.
      4. inaudible sound.
   2. In which range can sound be detected by the human ear?
      1. 0 to 20 Hz
      2. 20 to 20,000 Hz
      3. 20,000 to 40,000 Hz
      4. none of these
   3. A tabla is a
      1. string instrument.
      2. wind instrument.
      3. percussion instrument.
      4. reed instrument.
   4. Sound cannot travel in
      1. air.
      2. water.
      3. vacuum.
      4. solid.
   5. Sound travels fastest in
      1. solids.
      2. liquids.
      3. gases.
      4. vacuum.
   6. An echo is
      1. an absorbed sound.
      2. a reflected sound.
      3. dissonance.
      4. none of these
   7. The quality of sound is also referred as
      1. timbre.
      2. loudness.
      3. pitch.
      4. none of these
   8. The number of vibrations completed by a sound wave in one second is known as
      1. time period.
      2. amplitude.
      3. frequency.
      4. loudness.
   9. The minimum distance required for an echo to be heard is
      1. 10 m.
      2. 17 m.
      3. 27 m.
      4. 34 m.
   10. In which of the following is the speed of sound least?
       1. Aluminium
       2. Sea water
       3. Brass
       4. Granite
2. 2.

   Fill in the blanks.

   1. The frequency of vibration between 20 Hz to 20,000 Hz is the _______________ range of the human ear.
   2. Sound travels in the form of _______________________.
   3. A _____________________ is an example of a percusison instrument.
   4. The sound produced by vibrating an air column inside the hollow part of the instruments are called ____________ instruments.
   5. Reflected sound is called an _____________________.
   6. A sound wave with higher amplitude will produce a _________________ sound.
   7. Unpleasant sound that is very loud is called ___________________.
   8. Sound travels fastest through ______________ and _______________ decibel.
3. 3.

   Define Sound.

4. 4.

   Define SONAR.

5. 5.

   Define Echo.

6. 6.

   Define Oscillation.