An isotropic point source of sound waves is emitting sound waves of power `314 W` in spherical wave fronts, If the sound source is located at the point (`1`, `2`, `3`), the intensity at point [`4`, `6`,`(3+5sqrt(3))`], if all co-ordinates are measured in meters is :-

Options

A. `1 w//m^(2)`
B. `0.5 w//m^(2)`
C. `0.25 w//m^(2)`
D. none of these

Explanation

`(vecr_(2)-vecr_(1))=sqrt((4-1)^(2)+(6-2)^(2)+(3+5sqrt(3)-3)^(2))=sqrt(9+16+75)=10m`
`I=(P)/(4pi)*(1)/(r^(2))=(314)/(3.14xx4)xx(1)/(100)=0.25w//m^(2)`