Experiment
Conclusion:
- The angle of incidence, i is equal to the angle of reflection, r.
- Sound waves obey the law of reflection. That is, the angle of incidence is equal to the angle of reflection.
Q & A
Why hard plywood is used?A hard surface is a good sound reflector. Hard plywood is used so that only very little energy is lost during the reflection.
Q & A
Why mechanical stop watch is used as source of sound?Because its sound is not loud enough to be heard directly by the observer.
Q & A
Why cardboard tube is used?The cardboard tube is used to help to direct the incident and reflected sound waves.
Q & A
Why soft wood is used?The soft wood can absorb any sound from the stopwatch and prevent it from reaching the observer.