Q113 / 150 · MHT CET 2007 · Physics
Sound waves are not transmitted a long distance because
- Correct answerAthey are absorbed by the atmosphere
- Bthey have constant frequency
- Cthe height of antenna required should be very high
- Dvelocity of sound waves is very less
Solution
There are several factors which affect the propagation of sound. These are geometric spreading, atmospheric effect and surface effects. There are two mechanisms by which acoustic energy is absorbed by the atmosphere. These are molecular relaxation and viscosity effects. The amount of absorption depends on the temperature and humidity of the atmosphere. Note Under normal circumstances atmospheric absorption can be neglected except where long distances or very high frequencies are involved.
Hence, the correct answer is option: 'A'.