If the amplitude of waves at a distance `r` from line source is `A`. The amplitude at a distance `4r` will be

If the amplitude of a wave at a distance r from a point source is A , the amplitude at a distance 2 r will be

Amplitude of a wave .

If A is the amplitude of the wave coming from a line source at a distance r, then :

If A is the amplitude of the wave coming from a line source at a distance r, then :

IF A is the amplitude of the wave coming from a point source at distance r then

The amplitude of electric field at a distance r from a point source of power P is (taking 100% efficiency).

The amplitude of electric field at a distance r from a point source of power P is (taking 100% efficiency).

A point isotropic source generates sound oscillations with frequency v=1.45 kHz . At a distance r_(0)=5.0 m from the source the displacement amplitude of particles of the medium is equal to the a_(0)=50 mu m, and at the point A located at a distance r=10.0 m from the source the displacement ampitude is eta=3.0 times less than a_(0) . Find : (a) the damping coefficient gamma of the wave, (b0 the velocity oscillation amplitude of particles of the medium at the point A .