MCAT Physics Question — Absolute Pressure
- by
- Apr 17, 2017
- MCAT Question of the Day
Click for Explanation
The atmospheric pressure exerted on the surface of the fluid is equal to 101,000 N/m2 (1 atm). To calculate the gauge pressure at each point, you must apply the formula, Pgauge = ρgh, where Pgauge is the pressure due to the water column of height h, ρ is the density of the fluid, g is the gravitational acceleration constant, and h is the depth.
Pabs (A) = Patm + Pgauge (A)
Pabs (A) = (101,000 N/m2)+ ρwaterghA
Pabs (A) = (101,000 N/m2) + (1000 kg/m3)(10 m/s2)(10 m)
Pabs (A) = 201,000 N/m2
Pabs (B) = Patm + Pgauge (B)
Pabs (B) = (101,000 N/m2)+ ρwaterghB
Pabs (B) = (101,000 N/m2) + (1000 kg/m3)(10 m/s2)(30 m)
Pabs (B) = 401,000 N/m2
Therefore, the PB = 2PA making answer choice A the correct answer. Furthermore, an increase in depth of 10 m in water equals 1 atmosphere. Therefore, the total pressure at A is 2 atm while the total pressure at B is 4 atm.
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 expert 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 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
Submit a Comment