An amplifier supplies 5.0 Watts to a perfectly efficient loudspeaker at one end of a 10.0 cm diamter tube filled with air.
What is the intensity of the sound at the other end of the tube?
What is the intensity 10 m in front of the tube (approximate the wavefront to be a hemisphere moving outward in the direction that the loudspeaker is pointing). If the frequency of the sound is 250 Hz, how far apart are the wavefronts? The speed of sound is 340 m/s.