Advertisements
Advertisements
Question
Explain reflection at the boundary of a rarer medium.
Advertisements
Solution
- Consider a wave travelling in a solid medium striking on the interface between the solid and the air. The compression exerts a force F on the surface of the rarer medium.
- As a rarer medium has smaller resistance for any deformation, the surface of separation is pushed backward.
- As the particles of the rarer medium are free to move, a rarefaction is produced at the interface. Thus, compression is reflected as rarefaction and a rarefaction travels from right to left.
Reflection of sound at a rarer medium
APPEARS IN
RELATED QUESTIONS
Name the characteristic of sound in relation to its waveform
State the use of echo by a bat, dolphin and fisherman.
Name the waves which are used in sonar to find the depth of a sea. Give one reason for their use.
What is the shape of a soundboard kept behind the speaker on the stage of a big hall ?
Draw a labelled diagram to show the multiple reflections of sound in a part of the stethoscope tube.
Explain how is the principle of echo used by
(a) The bat during its flight at night,
(b) The dolphin to locate small fish as its prey.
What do you mean by reflection of sound? State one condition for the reflection of a sound wave. Name a device in which reflection of sound wave is used.
Define the term Frequency (as applied to sound waves)
Mention two properties of a wave, one property which varies and the other which remains constant when the wave passes from one medium to another.
What is meant by echo depth sounding?
Name the type of waves that are used for sound ranging. Why are radio waves not audible to us?
Explain Reflection at curved surfaces.
What is meant by an echo? Explain.
Match the following:
| 1. | Stethoscope | a. | Repeated reflections |
| 2. | Echogram | b. | Multiple reflections |
| 3. | SONAR | c. | Ultrasonic waves |
| 4. | Reverberation | d. | Speed of underwater objects |
