Question

Please do note write in cursive! Write neat!

Q19. Find out what ultra-sound is. What are applications of ultra-sound?

Q20. Go to this web-site http://newt.phys.unsw.edu.au/jw/hearing.html and check out your hearing, the hearing of a very young family member or friend, and the hearing of an older family member or friend. NOTE from the web-site: The instructions for using this service are given below the graphic. Repeat: do not start in the top third of the chart.

Report here about the findings for three different people: What are the lowest and the highest frequencies that the person can hear and what is the loudness level in decibels? How much do these frequencies differ between the three people that you measured? Find out if there is a reason behind these frequencies being different.

Answer 1

The audible sound for the humans is in the range of 20 Hz to 20,000 Hz. If the frequency of sound waves are higher than the upper audible limit, then the sound is called "Ultrasound"

In medical, the ultrasound waves for "Imaging" i.e.they are used to study the internal structure od the body. Ultrasound waves are mainly used in obstetrics, pelvic organs, gynecology and cardiology (Used to study the soft tissues of human internal structures).

In industry, the ultrasounds are used in Non-distructive testing (They study the internal cracks, pores inside the metallic structures Ex: testing the quality control in gas pipe lines)