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CBSE Class 9 Answered

1.   A sound wave has a frequency of 5000Hz and wave length of 20cm .how long will it take to travel 1Km.
Asked by M.s.srinidhi21 | 04 Mar, 2015, 06:08: PM
answered-by-expert Expert Answer

Hi Shrinidhi,

begin mathsize 14px style The space speed space of space sound space wave space is space given space as straight v equals nλ therefore straight v equals 5000 cross times 20 cross times 10 to the power of negative 2 end exponent equals 1000 space straight m divided by straight s Hence comma space the space time space taken space by space the space wave space to space travel space 1 space km space is straight t equals straight d over straight v equals fraction numerator 1000 space straight m over denominator 1000 space straight m divided by straight s end fraction equals 1 space straight s end style

Answered by | 04 Mar, 2015, 06:13: PM

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CBSE 9 - Physics
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