Page 204 - AWSAR 2.0
P. 204

 180 || AWSAR Awarded Popular Science Stories - 2019
Sound: It Shows, It Cures
  Mr. Aliarshad Kothawala*
Email: aliarshadiit@gmail.com
Sound is a physical phenomenon that humans and many animals can sense. Sound is a vibration. Sound and light are
twins and share many common properties. Just like light, sound also gets reflected, refracted, and diffracted. However, sound cannot be polarized! It reminds me of the childhood experiment many of us have conducted where we focused the rays of the sun using a magnifying glass on a piece f paper. The magnifying glass helps to concentrate these rays on to a very small region of the paper and igniting it. ! Then the question which naturally arises in one’s mind is that “Can sound be focused? “If yes, “Can it burn the object which is the point of focus? “ The answer is ‘Yes’. It is possible to focus sound. The object should possess the property to absorb maximum
amount of sound energy that is incident on its surface. If the object has the absorbing ability, the incident sound energy can be converted to heat energy. This heat so produced can cause burns. The advantage of this technique is that the heating happens only at the point of focus. If you try to place the object anywhere away from the focus, the object remains unaffected.
This can have an enormous advantage in the medical field. Just imagine destroying tumours using focused sound. This can be done using ultrasound, sound that has frequencies typically of ~1000000 Hz. The cancerous tumour that is located deep inside the body can be destroyed using heat created by focused ultrasound waves. Thus, sound enables treatment of cancer tumours, this technique is called “High Intensity Focused
 * Mr. Aliarshad Kothawala, PhD Scholar from Indian Institute of Technology, Madras, is pursuing his research on “High- Intensity Focused Ultrasound”. His popular science story entitled “Sound- It Shows - It Cures” has been selected for AWSAR Award.


























































































   202   203   204   205   206