3. A work station is to be located 3 m from a conveyor belt generating a...
3. A work station is to be located 3 m from a conveyor belt generating a sound power of 0.004 W, 4 m from a machine with 0.005 W sound power, and 6 m from a machine with 0.009 W sound power. Calculate: (a) the noise level at the work station if the sources rest on a hard surface but there are no sound reflections from walls or ceilings (b) the noise level at a work station 1m closer to the two machines and 2m farther from the conveyor belt.