Go to Home Page
You are here
Go to Reference Section
Go to Directories Section
Go to Community Section
Go to Fun Section
Go to Science Store
Go to About PhysLink.com
Top Destinations Menu
 Ask the ExpertsAsk the
Experts

 Physics Job BoardPhysics
Job Board

 Physics and Astronomy Departments DirectoryUniversity
Departments

 FREE Einstein eCardsEinstein
eGreetings

 PhysLink.com Science eStoreScience
eStore


Local in California?
Visit one of our retail stores.
XUMP - Science Toys





4th Of July Blowout Sale: Hurry! While Quantities Last!

   Question

When a flame comes out of a lighter on earth, it points up; which way would it point in a zero g environment?

Asked by: Chad Fultz

Answer

Flame in space in zero gThe short answer - It wouldn't point up, it would just form a burning ball right on the end of the lighter. The 'why' is fairly simple upon reflection, but not particularly intuitive. The burning of gas is it's combination with an oxidant, and the release of energy raises the temperature of the gas (hence 'heat rises'). The warm gas has a lower density than the air around it, and thus flows toward a region of lower density, i.e. - away from the gravitational pull of the Earth. In orbit, the net effects of gravity are balanced by the acceleration around the Earth. Thus, the warmed gases expand equally in all directions, and consume oxygen from the atmosphere equally in all directions. The fire will burn in a ball, outward in a growing sphere. It will usually burn faster than it can supply itself with oxygen, and burn out in a short period of time.

Further reading:

Answered by: Frank DiBonaventuro, B.S. Air Force Officer, Tinker AFB, OK


go to the top  
All rights reserved. © Copyright '1995-'2008 PhysLink.com
Win an Apple iPod Touch 32GB! Or one of Einstein Stuff Packs worth over $50! Enter our Einstein Look-a-Like Photo Contest! Click here for more details.