I would like to find out how much gas I can produce by electrolysis using homemade stuff. Is there any cost efficient/accurate way to measure the quantity of gas produced? [more inside]
posted by pigelb on Jul 16, 2008 - 6 answers

What else can be sensed passively? [more inside]
posted by viewofdelft on Jul 17, 2007 - 17 answers

Would a bag collapse if I sucked the air out of it in outer space? [more inside]
posted by TimeTravelSpeed on Sep 8, 2006 - 32 answers

How much lower is the air pressure on the 23rd floor of a standard apartment building than at ground level? [more inside]
posted by onshi on Dec 19, 2005 - 21 answers