LEARNATHON
III

Competition for grade 6 to 10 students! Learn, solve tests and earn prizes!

Learn more

Theory:

Like a rubber ball bouncing off a wall, sound bounces off a solid or liquid medium surface. The reflection of sound waves requires a large obstacle that can be polished or rough.
The laws of reflection are:
  • The angle in which the sound is incident is equal to the angle in which it is reflected.
  • Direction of incident sound, the reflected sound and the normal are in the same plane.
Uses of multiple reflections of sound:
 
Musical instruments:
 
Megaphones, loudspeakers, horns, and musical instruments like the nathaswaram, shehnai, and trumpets are all designed to send sound in a specific direction rather than dispersing it. In these instruments, sound is reflected sequentially by a tube and a conical opening, guiding the majority of sound waves from the source forward and towards the audience.
 
megaphone-3292549_1920.jpg
Megaphone
 
Stethoscope:
 
A stethoscope is a medical device that listens to sounds produced by the human body. These sounds reach the doctor's ears through multiple reflections in the connecting tube in stethoscopes.
 
675px-Stethoscope.jpg
Stethoscope
Important!
The use of earphones for long hours can cause infection in the inner parts of the ears, apart from damage to the eardrum. Your safety is in danger if you wear earphones while crossing signals, walking on the roads and travelling. Using earphones while sleeping is all the more dangerous as the current is passing in the wires. It may even lead to mental irritation. Hence, you are advised to deter from using earphones as far as possible.
Reference:
https://commons.wikimedia.org/wiki/File:Stethoscope.jpg
https://pixabay.com/photos/megaphone-device-loudspeaker-3292549