Part A: A spherical wave with a wavelength of 4.0 m is emittedfrom the origin. At one instant of time, the phase at r = 8.0 m isπrad. At that instant, what is the phase at r = 7.5 m ? Expressyour answer to two significant figures and include the appropriateunits.
Part B: What is the phase at r = 9.5 m at the same instant?Express your answer to two significant figures and include theappropriate units.
2. The sound intensity 54.0 m from a wailing tornado siren is0.140 W/m2 .
Part A: What is the intensity at 1150 mm ? Express your answerwith the appropriate units.
Part B: The weakest intensity likely to be heard over backgroundnoise is ≈1μW/m2. Estimate the maximum distance at which the sirencan be heard.
Express your answer with the appropriate units.
