This is a topic covered under the Chapter 12 of NCERT which is Sound.
This video is thorough explanation about the reflection of Sound and its phenomena which are echo and reverberation.
We have explained the use of reflection.
Moving ahead we discussed about hearing range of human ear which is 20Hz – 20KHz.
Below 20Hz, sound is infrasonic and went undetectable by the human ear.
Above 20 KHz sounds are called ultrasound and we are not able to hear it.
We studied the uses of Ultrasound – how it is used to make an image of our internal organs and how it is used o detect the flaws and cracks in the iron blocks.
Upcoming videos will be explaining about #SONAR and other uses of sound and its #phenomena.
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