MCAT Physics Question — Mercury Pressure
- Aug 21, 2014
- MCAT Question of the Day
- Reviewed By: Liz Flagge
A column of mercury (S.G.13) is twice the height of a column of water. What is the difference in pressure at the bottom of the mercury column in comparison with the column of water?
a) the same
b) twice as great
c) 13 times as great
d) 26 times as great
The formula for pressure at the bottom of a column of fluid is P=ρgh where ρ is the fluid density. Specific gravity is the ratio of fluid density to water density. Since the mercury is 13 times as dense as water and the column is twice as tall, the pressure will be 26 times as great.
a) the same, incorrect, Pressure at the bottom of a column of fluid depends on the fluid density and height of the column.
b) twice as great, incorrect, This answer neglects the difference in specific gravity.
c) 13 times as great, incorrect, This answer choice neglects the doubled height of the mercury column.
d) 26 times as great, correct.
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 ConsultationSchedule Now
Free MCAT Practice AccountNeed 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