MCAT Physics Question — Distress Signals
- by
- Dec 09, 2014
- MCAT Blog, MCAT Physics, MCAT Question of the Day
- Reviewed By: Liz Flagge
Distress signals in the form of light and sound are emitted from a submerged submarine. When the signals enter the atmosphere, what happens to the speed of sound and light, respectively?
A) The speed of sound and light both increase
B) The speed of sound and light both decrease
C) The speed of sound increases and the speed of light decreases
D) The speed of sound decreases and the speed of light increases
Explanation
This question is testing your understanding of optical properties and characteristics of sound. Light travels faster in less dense mediums. Therefore, when light goes from water to air, it speeds up. Oppositely, sound travels faster in more dense mediums, which can be represented by the equation vsound = (B/ρ)1/2, where B is the bulk modulus and ρ is the density of the medium. While the ρgas < ρliquid < ρsolid, the Bgas << Bliquid << Bsolid. Therefore, vsolid > vliquid > vgas. Since the sound waves are travelling from liquid to gas, they will slow down making D the correct answer.
Want more MCAT practice?
We’ve got options for every schedule and learning style!
From the best online MCAT course created by top instructors with 524+ MCAT scores to the most representative full-length practice exams and private tutoring, we can custom tailor your MCAT prep to your goals!
Not sure which option is right for you? Schedule a free MCAT consultation with an MCAT Advisor using the form below. No obligation, just expert advice.
Search the Blog
Free Consultation
Interested in our Online MCAT Course, One-on-One MCAT Tutoring or Med admissions packages? Set up a free consultation with one of our experienced Senior Student Advisors.
Schedule NowPopular Posts
-
MCAT Blog What's on the MCAT?
-
MCAT Blog How to Review MCAT Full Lengths

Free MCAT Practice Account
Need great MCAT practice?Get the most representative MCAT practice possible when you sign up for our free MCAT Account, which includes a half-length diagnostic exam and one of our full-length MCAT practice exams.
Learn More