Question

p.8.6 summative
a recording studio is being designed to prevent sound echoes. engineers line the walls with thick foam panels. which statement best explains why this material is used?
foam increases the frequency of sound waves, making the room louder.
foam reflects most sound waves, causing the sound to bounce around the room.
foam transmits sound waves, allowing them to pass through the walls easily.
foam absorbs sound waves, taking in their energy and lowering amplitude, which prevents echoes.

Explanation:

To prevent echoes, sound waves should not reflect. Thick foam panels are used in recording studios because they absorb sound waves. Absorbing sound waves means the foam takes in the sound's energy, which lowers the amplitude (loudness - related property) of the sound waves. This stops the sound from reflecting (echoing) off the walls. The other options are incorrect: increasing frequency (first option) doesn't relate to preventing echoes; reflecting sound (second option) would cause more echoes; transmitting sound (third option) would let sound out, not prevent echoes inside the studio.

Answer:

The correct option is: "Foam absorbs sound waves, taking in their energy and lowering amplitude, which prevents echoes."