Sound travels fastest through:
d) the speed of sound is constant in all mediums
Sound travels fastest in the solid medium, glass, because of the close proximity of molecules and the strength of the intermolecular bonds. Sound is faster in water than air, but fastest in the solid medium. As a rule of thumb, sound travels faster as the density of the medium increases. However, some liquids have a faster speed of sound transmission than some solids. You are unlikely to encounter such a relationship on the MCAT. For the MCAT, assume speed of sound is fastest in the most dense medium unless explicitly instructed otherwise by the question or passage.
a) water, incorrect, Speed of sound in faster in water than air, but glass is fastest.
b) air, incorrect, Speed of sound in air is the slowest of the choices because air is least dense.
c) glass, correct.
d) the speed of sound is constant in all mediums, incorrect, Speed of sound increases as medium density increases.