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A small speaker has a capacity of power 3 W. A microphone is placed at distance 2 m from the speaker. Fine the displacement amplitude of particles of air near to microphone. The frequenct of sound emitted bt speaker is 1.0 KHz (Density of air = 1.2 `kg//m^(3)` and speed of sound in air = 330 m/s)A. `2.76xx10^(-4)cm`B. `4xx10^(-4)cm`C. `10xx10^(-4)cm`D. `3.8xx10^(-3)cm`

Answer» Correct Answer - A
`becauselp/(4pir^(2))=3/(4pixx2^(2))=3/(16pi)`
But `l=2pi^(2) A^(2)v^(2)p_(o)c` or `A^(2)=l/(2pi^(2)v^(2)p_(o)c)`
`therefore" "A=sqrt(((l)/(2pi^(2)v^(2)p_(o)c)))=sqrt((3)/((16pixx2pi^(2)xx10^(6)xx12xx330)))`
`0.002764xx10^(-3)m=2.76xx10^(-4)cm`


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