

Relating Presure
Name: Hildie K.
Status: Education
Age: 30s
Location: N/A
Country: N/A
Date: 20002001
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 400thousand footpounds 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 footpounds 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 footpounds 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.
400thousand ftlbs 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
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Update: June 2012

