Department of Energy Argonne National Laboratory Office of Science NEWTON's Homepage NEWTON's Homepage
NEWTON, Ask A Scientist!
NEWTON Home Page NEWTON Teachers Visit Our Archives Ask A Question How To Ask A Question Question of the Week Our Expert Scientists Volunteer at NEWTON! Frequently Asked Questions Referencing NEWTON About NEWTON About Ask A Scientist Education At Argonne Chewing Gum and Air Pressure
Name: Kristine J.
Status: educator
Age: 20s
Location: N/A
Country: N/A
Date: Monday, September 30, 2002


Question:
One of my students asked how and why chewing gum during a flight makes your ears pop. I didn't have the answer, but told him I would try to find out. If you have any information for me, I would greatly appreciate it. Thank you, Kristine J.


Replies:
Kristine,

Chewing gum during a flight does not make one's ears pop. Rather, it is the swallowing that equalizes the throat/inner ear air pressure via the ear's Eustachian canal that makes the sound one hears. Swallowing repeatedly as the plane is pressurized repeatedly opens the ear-to-throat connection to ease the pressure difference on either side of the eardrum. The suggestion that one chew gum is simply a way to encourage the swallowing action.

Regards,
ProfHoff 486


The popping during an air flight isn't due to the chewing gum, but is due to any swallowing action while chewing. The air pressure in an aircraft, in flight, is about 50% of sea-level pressure. The popping is just the equalizing of air pressure between the air around the passenger and the pressure in the passenger's inner ears. When a person swallows, the tubes from the back of the mouth to the ears open, hence the equalizing of the two pressures and much relief to the air passenger. Now you know why they hand out lollies on board, just before descending.

Howard Barnes


The pop you hear is the air entering or escaping from the inner ear when the tube connecting your throat with the inner ear opens. You only hear the popping when there is an unequal pressure on the inside and outside... as in when you are climbing in the atmosphere to where the pressure around you is less or descending to where the pressure is greater.

The tube is normally closed, but opens when you yawn, sneeze, or swallow. Chewing gum causes you to swallow more often opening the tube and causing the pop.

Every day the atmospheric pressure changes, but usually it is a slow enough change and we swallow often enough to make the change in pressure come in small enough increments that we do not notice the happening.

Larry Krengel


This has to do with the structure of the ear. The eardrum separates the middle ear from the outer ear. When you go up in a plane, the atmospheric pressure drops as you increase the elevation. The pressure outside your ear drops faster than the pressure inside your ear. You have two small passage from your throat called the Eustachian tubes, one leading into each middle ear. When you open your mouth wide, i.e., drop your jaw, it opens these passages a little wider. This allows the buildup of pressure in your middle ear to be released and you feel a "pop." Chewing gum causes you to open and close your mouth and to move your jaw around. Incidentally, this is also the reason why small children get middle ear infections more often than adults-their Eustachian tubes are shorter and at a shallower angle than they are by adulthood. So, there is a more direct passage into the inner ear for bacteria from the throat.

Van Hoeck


There is a long, narrow tube connecting the middle ear to the back of the pharynx. The purpose of this tube is to equalize the pressure on both sides of the eardrum. When the pressure outside changes rapidly, air is supposed to moves through this tube, but because the tube is narrow, it can easily be blocked or squeeze shut. Swallowing wiggles things around and can unblock the tube.

Tim Mooney



Click here to return to the General Topics Archives

NEWTON is an electronic community for Science, Math, and Computer Science K-12 Educators, sponsored and operated by Argonne National Laboratory's Educational Programs, Andrew Skipor, Ph.D., Head of Educational Programs.

For assistance with NEWTON contact a System Operator (help@newton.dep.anl.gov), or at Argonne's Educational Programs

NEWTON AND ASK A SCIENTIST
Educational Programs
Building 360
9700 S. Cass Ave.
Argonne, Illinois
60439-4845, USA
Update: June 2012
Weclome To Newton

Argonne National Laboratory