Video Gallery

Gas Pressure and Converting Unis of Pressure

Go to Video Gallery Added Mar 22, 2019 •

Copy this URL:
Embed code:	<iframe class="edlio-embed-player" type="text/html" width="640" height="360" src="//www.macs.k12.pa.us/apps/embed/?v=212301" frameborder="0" allowfullscreen></iframe> Change dimensions

Go HD

Here is a video that might help you in doing pressure conversions for your project.

Show Transcript

in this video we're going to learn about gas pressure pressure can be defined as the force exerted by a substance per unit of area on another substance so you can think of it as when you walk down the sidewalk every time you take a step your shoe is going exert pressure on the sidewalk and the area that your shoe exerts a pressure on is going to be equal to the area of the bottom of your shoes so it's confined to that space and we usually measure the pressure in units Newtons per meter squared in the unit Newton is going to be a unit of force and then meter squared is a unit of area now gas pressure can be thought of the the force of the gas particles as they collide with the walls of a container with a gas inside of it so when you blow up a balloon the reason the balloon holds its shape is that the pressure inside the balloon is greater than the outside of the balloon now there's gas pressure all around us we don't notice it because we're used to it but there are billions and billions of gas particles colliding with us all the time these particles are also colliding with the outside of the blind you can see the purple particles here rubber the external pressure the pressure just of the atmosphere now those particles are colliding with the blue and trying to deflate it but the particles on the inside of the balloon that's these yellow ones here are colliding with greater frequency because they're a lot of particles confined to a small area and so the balloon is able to hold its shape that we measure pressure gas pressure in units of Pascal's and on the earth at sea level there would be about 100 1000 pascals to pascals are actually a really small units compared to the standard atmospheric pressure when other words the pressure of all this atmosphere above us so since Pascal's are so small we usually use kilopascals instead and we use the symbol kPa to to describe kilopascals all we have to do is divide this number by 1000 and we'll get the standard atmospheric pressure in kilopascals and so this is usually shown in text books as 101.3 kPa others other units of pressure as well that we measure Standard air pressure in one of the most common units is called atmospheres and we abbreviate at ATM no atmospheres are really nice unit because at sea level the standard atmospheric pressure in atmospheres is going to be one atmosphere because there's a literally one whole atmosphere above you so it works really nice is one other unit that we use a lot to measure air pressure and that's called millimeters of mercury millimeters of mercury is based on a device called a barometer and a barometer is a device that measures air pressure that the old style barometer consisted have a tube that was filled up with Mercury at this to represents right here and the bottom of the tube would have been open and submerged in this big container of more Mercury out of mercury stays inside the tube just like when you put your finger on top of a straw put it into your drink and then the drink would stay inside the Strand Till You released your finger from the top so as the air pressure increases in the atmosphere there would be more Force pushing down on mercury in this container and that would cause the Mercury to rise up higher in the stew now at standard pressure when scientists measure this when they first created it and measure the amount of mercury inside this too big found that it was 700 60 millimeters of mercury and so this is our other unit that we use this is standard pressure in millimeters of mercury we also use the Tor and millimeters in Mercury and tour are going to be the exact same thing 760 so how do we convert between these units how do they all relate to one another well one atmosphere is going to be the same thing or another words equal to 101 2.3 kilopascals which is going to be the same thing or another is equal to 760 mL of mercury now we can use this relationship right here as a conversion factor we can create conversion to be able to solve problems so let's take this over here and use this to solve this problem right here so this question is asking us to convert 45.6 kilopascals in the units of atmospheres and then to convert that also into units of millimeters of mercury we're going to use this little relationship that we created to solve this problem when I like to read a problem a word type problem in science I like to underline some of the information here underline the given information in green this is just to help keep organized and then underline the information that they questions asking for and read so we're converting to atmospheres and millimeters of mercury this is what I know when I saw conversion problem I was like to solve it the same way I first start by just writing down the given information with the appropriate unit so here's the information I'm given in the problem and what I'm going to do is on a x this at this buy a conversion factor in the conversion factor is just a fraction that has the new units that we want to end up with we're going to put that on the top and it has the old unit that we want to get rid of in this case we're trying to get rid of KP her being left with atmospheres when we do it like this with a conversion factor you see the same unit on top and bottom like this we can cross them off will be left with units of atmospheres all we have to do now is look at our relationship stop here and take these numbers that correspond to these units and just plug them into our conversion factor so you see I literally just took those numbers out of that relationship plug them in and now I'm going to do the math I just take 45 point one and I multiply that by one over 101.3 another words I take 45.6 and I'm going to divide it by 101.3 and I'm going to get an answer of 0. 459 atmospheres and so there's the answer the first part of the question I'm just going to take that original number again and this time I'm going to convert it into millimeters of mercury to the same thing where I'm going to conversion factor the new unit I want is millimeters of mercury to put that on the top the unit I want to get rid of is kPa going to put that on the bottom and then once again I'm going to look at my relationship I'm going to take those numbers out talk to men tell 760 millimeters of mercury is the same thing as 101.3 kilopascals on your calculator you can take the original Amber 45.6 you multiply that by 760 you get answer the divide that answer by 101.3 and you should end up with 349 millimeters of mercury and so that is gas pressure and those are three give the most common units we use in gas pressure and how to convert between those units

Uploaded by Nathaniel Pettinato.

Video Gallery

Gas Pressure and Converting Unis of Pressure

Popular Videos