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21 December 2001

Readers Respond

Sub-zero Bubble Blowing

I really loved Francis C. Van Asten's article about blowing bubbles in cold air. My only regret was that I was not able to send him a note of thanks because there was no E-mail address with the piece and I could not find him on the forum. Ben and I spent some time today blowing bubbles in air at about 29 degrees Fahrenheit. Not the dramatic effects Francis described but wow! The bubbles really zoomed high in the air relative to what we experienced in the warmth of summer. The only warning I would give is to be careful about freezing your fingers in all the excitement!

Peter Baum

Addendum- Ben and I went out this morning while it was snowing to see what would happen if we blew bubbles under those conditions. The flakes either bounce off the bubbles or slide down (or perhaps sometimes move through) the bubble to rest at the bottom. None of the bubble popping I feared. The added weight slows the bubbles so they end up moving downward fairly soon and encounter the falling flakes even less frequently.

Thrilled by the fast rising bubbles in cold air, I've been thinking about trying to fill the bubbles with hotter air since I don't have any lighter gas handy. A candle flame doesn't appear to create enough force to form the bubble or even support a bubble through a small opening but I've been thinking about using an electric hair dryer. My wife said she thought she had one around somewhere! Regards, Peter

Editor's Note: Francis Van Asten can be reached at fvanasten@qwest.net. -sg

 

Celebrating Franklin's Kite Experiment

Dear Shawn,

Any event should include some celebration/ demonstration at the site of the Isamu Nagouchi Sculpture which celebrates Franklin's discovery that Lightning is an Electric Fire. This is on the Philadelphia side of the Benjamin Franklin Bridge!. It is a steel kite and key, and it is magnificent! You might also include the Franklin Institute in preplanning/funding/public awareness for your observance of an important anniversary. Ben Franklin continues to be the First Citizen of Philadelphia.

I love this thing you created in SAS!

Sincerely,

Bob Hirsh, M.D.

 

Franklin's kite experiment is an icon of amateur science. I'm imagining nice printed tee shirts. I just recently opened up a screen printing shop and can use some work. If you decide on having any shirts printed, please give me an opportunity to be of service. Thank you and God bless you.

Sincerely,

John Lugo Jr.

 

Hi Shawn -

Let me be the two hundredth SAS member to suggest that we go fly a kite!

Perhaps the federal government or some state governments might declare June 2002 as National/State Kite Flying Month. While the focus might seem slightly off of Ben Franklin per say, it could cause at least some attention to amateur science. Know your legislator? How about getting SAS members to write their own congressional member proposing same?

Would be especially nice if home made kites could be emphasized.

Perhaps SAS could sponsor a kite design contest; not an easy challenge to create a truly NEW design as this has been done many times before.

SAS projects on analyzing why/how kites fly in some manner. I am certain, for example, that box kites DO NOT fly; merely an optical allusion. :-}

I wonder if there is an identifiable critical stability point for the mass and drag of a kite tail verses the sail area of the kite? Would such a stability point be related to or independent of wind velocity?

Robert Shelton