Three concentric spherical shells are cut in half so that only the lower halves of the shells are visible. The inner shell, middle shell, and outer shell have radii of 1 m, 2 m, and 3 m, respectively.
Four lines extend from the center and extend outwards through each shell.
The intersection of the four lines with the inner shell, labeled "1", are the four corners of a square with a curved face that lies on the surface of the sphere.
The intersection of the four lines with the middle shell, labeled "1/4", are the four corners of a square with a curved face that lies on the surface of the sphere. A grid divides this square into four smaller squares that are each the same size as the square on the inner shell.
The intersection of the four lines with the outer shell, labeled "1/9", are the four corners of a square with a curved face that lies on the surface of the sphere. A grid divides this square into nine smaller squares that are each the same size as the square on the inner shell.
Indicate over how many squares the sound waves would spread for
r = 7 m.
squares
The sound intensity would decrease to what fraction in value?