FreeMCATPrep Logo

More Than 475 Free MCAT Questions with Detailed Answers!

Click HERE for your Random Question from our MCAT Question A Day Archive

MCAT Question A Day - 2/17/14 - Answer!

The speed of sound in air at a given temperature is 360 m/s. What is the shortest closed-end pipe that will produce an air column length that can resonate at a frequency of 450 Hz?

A.  20 cm
B.  80 cm
C.  90 cm
D.  125 cm

The correct answer is (A). The shortest pipe length will be associated with the wavelength for the fundamental tone. For a closed-end pipe, this is: wavelength = 4L. The wavelength is the ratio of the speed to the frequency: wavelength = velocity/frequency. Therefore, the shortest length is:

L = velocity / (4*frequency) = (360 m/s) / (4*450/s) = 0.20 m = 20 cm

Want more questions? - Click here to check out our MCAT Question A Day archive