Relating Presure ```Name: Hildie K. Status: Education Age: 30s Location: N/A Country: N/A Date: 2000-2001 ``` Question: What can I compare with 25,000 pounds of force per square inch so the average person can relate to the measurement? What can be compared to 400-thousand foot-pounds of energy? Replies: Any object that would weigh 25,000 lbs resting on a 1 inch square block would exert 25,000 psi, or any gas in a container at that pressure would exert such a force. Off hand I cannot think of any object that would be a single inch and weigh that much except for a piece of the sun, but as mentioned above, an object such as a dump truck resting fully on a 1 inch square block would exert 25,000 psi on the ground. As for the 400 thousand foot-pounds of energy the only thing that comes to mind there would be a rocket engine perhaps from the shuttle. If you were explaining such ideas to children I would think of something using smaller numbers! Michael Baldwin Hildie, The area of the palm is about 4 inches by 4 inches: 16 square inches. 25,000 pounds of force per square inch is 400,000 pounds on the palm of your hand. An average weight for a human being is a little less than 200 pounds. 25,000 pounds per square inch would correspond to supporting the weight of over 2,000 people with just the palm of your hand. 400,000 foot-pounds of energy is required to raise that much weight a distance of just one foot. Dr. Ken Mellendorf Illinois Central College 1.) 25,000 lb(force) / square in = 25,000 psi = 1701 atm (times atmospheric pressure). This would also be the pressure below 17.1 km (10.6 miles) of sea water if such a place were to exist on the planet. The deepest depression on the Earth, the Marianas Trench, is only a mere 6.78 miles deep (15,982 psi or 1087 atm). 2.) 400,000 ft * lb(force) is enough energy to power a 100 Watt light bulb for about 90 mins and 23 seconds. Or it will power a 1500 Watt microwave oven for about 6 mins. -Darin Wagner 25,000 lbs / sq in => a football lineman wearing high heels the size of a pin head standing on your toe. A compressed gas cylinder is limited to ~ 3,000 lbs / sq in so I would imagine that 25,000 lbs / sq in would burst one of those. 400-thousand ft-lbs of energy => energy required to lift 400 lbs 1000 ft. How high is the Sears Tower? The lineman carry (himself and) his girlfriend up a 1000 ft flight of stairs with this amount of energy. Greg Bradburn Click here to return to the Physics Archives

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