Name: Hildie K.
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?
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
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.
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.
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Update: June 2012