A. When we are designing the sound levels to ensure a clear reception by a human ear, we often express the sound intensity in a unit called dB. The intensity level in dB of a sound wave can be found...

Extracted text: A. When we are designing the sound levels to ensure a clear reception by a human ear, we often express the sound intensity in a unit called dB. The intensity level in dB of a sound wave can be found by converting the sound intensity produced by the speakers, I, expressed in Watts/m², using the formula: B(dB) = 10log10G) Where: B is the sound intensity level in dB. I is the sound wave intensity in W/m². Io is a constant representing the intensity threshold of hearing, which is the lowest intensity a human can hear with his/her ears. A sound source, or a speaker, produces a wave with intensity I, which varies with respect to time as given below: 1 = 3+ 2 cos(4t – n) W/m². Knowing that I, = 1 × 10-12 W /m²: 1. Find a formula for the rate of change of ß with respect to time. [Hint: use the chain rule] 2. Find the value of the rate of change of ß with respect to time at t = 1 sec.