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Question
A sound wave is passing through air column in the form of compression and rarefaction. In consecutive compressions and rarefactions ______.
Options
density remains constant.
Boyle’s law is obeyed.
bulk modulus of air oscillates.
there is no transfer of heat.
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Solution
A sound wave is passing through air column in the form of compression and rarefaction. In consecutive compressions and rarefactions there is no transfer of heat.
Explanation:
- Due to compression and rarefactions density of the medium (air) changes. At compressed regions density is maximum and at rarefactions density is minimum.
- As density is changing, so Boyle's law is not obeyed.
- The bulk modulus remains the same.
- The time of compression and rarefaction is too small i.e. we can assume an adiabatic process and hence no transfer of heat.
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