Final answer:
Fiberglass is the material commonly used in acoustical ceiling construction for sound absorption. It reduces noise by trapping sound waves, and also serves as insulation against heat transfer.
Step-by-step explanation:
Acoustical ceilings are designed to absorb and control sound within a room. The most commonly used material for constructing acoustical ceilings that aids in sound absorption is fiberglass. This material helps to reduce the transfer of sound by trapping the sound waves within its dense fibrous structure, which minimizes both the reflective sound and the overall noise level in a space. Additionally, fiberglass is also used for insulation purposes to prevent heat transfer between the inside and outside of a building, contributing to its versatility in construction.
Sound behaves differently in various parts of a room. Specifically, sound is louder where constructive interference occurs, and softer in areas of destructive interference. Additionally, the perception of loudness can also be affected by the density of the material present, with sound being louder where the density is smallest and softer where the density is greatest.