Final answer:
The ear is remarkably sensitive to low-intensity sounds and can detect frequencies in the range of 2000 to 5000 Hz. The lowest audible intensity or threshold is about 10-12 W/m² or 0 dB.
Step-by-step explanation:
The ear is remarkably sensitive to low-intensity sounds. The lowest audible intensity or threshold is about 10-12 W/m² or 0 dB. Sounds as much as 10¹2 more intense can be briefly tolerated. Very few measuring devices are capable of observations over a range of a trillion.
The perception of intensity is called loudness. At a given frequency, it is possible to discern differences of about 1 dB, and a change of 3 dB is easily noticed. But loudness is not related to intensity alone.
The ear has its maximum sensitivity to frequencies in the range of 2000 to 5000 Hz, so that sounds in this range are perceived as being louder than, say, those at 500 or 10,000 Hz, even when they all have the same intensity.