Code Number: 1G20.10 

Demo Title: Candle in a Bottle

Area of Study: Mechanics

Equipment: 

Candle attached to the bottom of a large bottle.  Catch box with lots of padding.  

Procedure:

Light the candle, seal the bottle, and drop into a padded catch box.  The candle will stay lit during the whole drop and only go out when the bottle stops.  This is contrary to urban legend which says the candle will go out due to the fact that in freefall the air in the bottle does not circulate and when the nearest oxygen to the candle is used up, the candle will go out.  However, there is plenty of heat convection provided by the candle during freefall so the candle will stay lit. 

Note: that these references have the wrong explanation: Reprints from Articles from The Physics Teacher, April 1963 to Dec. 1971, # 4 Convection Currents, p. 1. and Julius Sumner Miller, Q66 & A66, Millergrams I – Some Enchanting Questions for Enquiring Minds, p. 44 & 100.

References:

  • "Figuring Physics", TPT, Vol. 39, #1, Jan. 2001, p. 22.
  • Donald D. Snyder, Bruce E. Lee, "Cohesion Plates and Convection Currents", AJP, Vol. 32, #1, Jan. 1964, p. 61.
  • Reprints from Articles from The Physics Teacher, April 1963 to Dec. 1971, # 4 Convection Currents, p. 1.
  • Julius Sumner Miller, Q66 & A66, Millergrams I – Some Enchanting Questions for Enquiring Minds, p. 44 & 100.
University of Maryland Physics Department QOTW Question #261
University of Maryland Physics Department QOTW Answer #261
1G20.10 - University of Maryland QOTW Answer #261 Part 1
1G20.10 - University of Maryland QOTW Answer #261 Part 2
1G20.10 - University of Maryland QOTW Answer #261 Part 3