The MSDS HyperGlossary: Pressure Unit Conversions
Pressure conversion is a free online calculator for converting metric and imperial units of pressure. Conversion between pascal, bar, atmosphere, torr. Conversion of pressure units Pa = newton per square meter is pascal force per area unit psi pounds per square inch - Eberhard Sengpiel sengpielaudio. State Pascal's principle. Understand applications of Pascal's principle. Derive relationships between forces in a hydraulic system. Pressure is defined as force.
Pascal's principle underlies the operation of the hydraulic press.
Pressure conversion - pascal, bar, psi, atmosphere, torr
The hydraulic press does not violate energy conservationbecause a decrease in distance moved compensates for the increase in force. When the small piston is moved downward centimeters, the large piston will be raised only one-fiftieth of this, or 2 centimeters. The input force multiplied by the distance moved by the smaller piston is equal to the output force multiplied by the distance moved by the larger piston; this is one more example of a simple machine operating on the same principle as a mechanical lever.
Pascal's principle applies to all fluids, whether gases or liquids. A typical application of Pascal's principle for gases and liquids is the automobile lift seen in many service stations the hydraulic jack. Increased air pressure produced by an air compressor is transmitted through the air to the surface of oil in an underground reservoir.
The oil, in turn, transmits the pressure to a piston, which lifts the automobile. The relatively low pressure that exerts the lifting force against the piston is about the same as the air pressure in automobile tires.
Now let's fill this thing with some liquid, which will be blue-- so that's my liquid. Let me see if they have this tool-- there you go, look at that.
I filled it with liquid so quickly.
This was liquid-- it's not just a fluid, and so what's the important thing about liquid? Let's take what we know about force-- actually about work-- and see if we can come up with any rules about force and pressure with liquids. So what do we know about work?
- Pascal's principle
- Pascal's law
Work is force times distance, or you can also view it as the energy put into the system-- I'll write it down here. Work is equal to force times distance.
We learned in mechanical advantage that the work in-- I'll do it with that I-- is equal to work out. The force times the distance that you've put into a system is equal to the force times the distance you put out of it.
And you might want to review the work chapters on that. That's just the little law of conservation of energy, because work in is just the energy that you're putting into a system-- it's measured in joules-- and the work out is the energy that comes out of the system. And that's just saying that no energy is destroyed or created, it just turns into different forms.
Let's just use this definition: Let's say that I pressed with some force on this entire surface. Let's say I had a piston-- let me see if I can draw a piston, and what's a good color for a piston-- so let's add a magenta piston right here. I push down on this magenta piston, and so I pushed down on this with a force of F1. Let's say I push it a distance of D that's its initial position. Its final position-- let's see what color, and the hardest part of these videos is picking the color-- after I pushed, the piston goes this far.Pascal's Law (Part 1 of 3)
This is the distance that I pushed it-- this is D1. The water is here and I push the water down D1 meters.
In this situation, my work in is F1 times D1. Let me ask you a question: How much total water did I displace? Well, it's this volume? This unit is used by meteorologists who find it easier to refer to atmospheric pressures without using decimals. Pressures of several gigapascals can convert graphite to diamond or make hydrogen a metallic conductor!
Pressure and Pascal's principle (part 1)
Such high pressures are rarely encountered in everyday life. If you ever perform a calculation of any sort, always remember to write the units next to each number in your calculation and make sure that they cancel properly. Further Reading More info about the metric systemincluding prefixes, at ChemTeam. Wednesday, August 10, This page is copyright by ILPI. Unauthorized duplication or posting on other web sites is expressly prohibited. Send suggestions, comments, and new entry desires include the URL if applicable to us by email.