We're not sure of the solution, so we'll post the work here, and let others
tear it apart:
Sound intensity is proportional to the inverse square of the distance from the source.
So the new sound intensity is ( 1/0.67 )2 times the original value.
db = 10 log(P2/P1) = 10 log (1/0.67)2 = 20 log (1/0.67) = -20 log (0.67) =
+3.479 dB
Check:
(all together now . . . everybody sing, dance, and wave your hands in the air)
That sounds about right . . . we know that 0.707 is 1/2 sqrt(2),
which would produce a change of 3 dB.
The image location is where the observer is sighting when viewing the image.
They are: concave (curved away from the observer) convex (curved toward the observer)
The hidden observer in hypnosis refers to the divided consciousness into two separate components.
This is due to the Doppler effect.
when position of the body with respect to an observer change with time then the body are said to be in motion.
New York City.
3
Pittsburgh is about 40° north.
The observer's location and the time of the year :)
5
The observer's location and the time of the year :)
The image location is where the observer is sighting when viewing the image.
at the poles
increasing wavelength
Left and right describe direction in terms of the observer. In contrast, the cardinal directions are independent of the observer's position.
Plattesburg;)
high tide i think