A propane tank by itself has no explosive force. Propane will only burn when mixed with oxygen. However you can create what they call a BLEVE from a propane tank (boiling liquid expanding vapor explosion). Basically you would heat up the propane tank (example house on fire, etc) and a reaction would occur causeing the tank to burst. There are other ways to do it but it gets really technical. Research BLEVE and you will fand many references about blast effects and fireball radius, frag radius etc. The following link gives you safe separation distances:
http://me.queensu.ca/people/birk/research/thermalHazards/bleve/safeDistance.php
propane has 21,548 BTU per pound so about 2 1/2 pounds per hour remember that propane is stored in a liquid and you need a big enough tank to allow the propane to change from a liquid to gas.
Propane burns 91,547 b.t.u.'s an hour per gallon of propane. Depending on the b.t.u. output of the appliance you are running you should be able to calculate how many hours you can use your tank.
0.862 tons of propylene per ton of propane
Furnace it has to reach much higher temperatures than the fireplace
rounded to the closest pound it is 495 pounds-force (lbf)
$15 a pound
propane has 21,548 BTU per pound so about 2 1/2 pounds per hour remember that propane is stored in a liquid and you need a big enough tank to allow the propane to change from a liquid to gas.
a typical steel "30 pound" liquid propane tank weighs about 25-28 pounds empty.propane tank markings (on collar)propane weighs about 4.125 pounds per gallon and a "30 pound tank" willhold about 7.5 gallons so a full tank will weigh about 55 pounds or so./source: wiki.answers.com/
no force, it has momentum
You cannot use output pressure to tell how full a tank is. The pressure will remain constant until it's just about out of propane. You can use weight, if you know how much it weighs when empty, and when full - then it's just simple math.
for a given lever length the force is (150 / 100) times greater torque = force (pounds) * lever length (feet)
Any force that is more than 50 pounds will lift a 50-pound object. The greater the force is, the greater the object's upward acceleration, and the sooner the object will reach any given height.
This site: http://www.pmak.org/public/propane_facts.html states the following: The specific gravity of propane liquid is 0.504; water is 1. Therefore 1 litre of propane weighs 0.504kg. (1 litre of water weighs 1kg)
25 newtons
0.862 tons of propylene per ton of propane
Furnace it has to reach much higher temperatures than the fireplace
Propane burns 91,547 b.t.u.'s an hour per gallon of propane. Depending on the b.t.u. output of the appliance you are running you should be able to calculate how many hours you can use your tank.