Air Definition and 1000 Threads

If you had a rotating object like a tire or barrel that you wanted to distribute compressed air to while it's rotating, what would some ways to do it? One way I'm thinking is just a tight seal at the axis, but then there would be a lot of friction. Any other ideas??

Hi guys Im trying to understand something.. If air is coming through a pipe, at a variable fan speed. (0.0053 m3/s) and the pipe is 10 meters long and coiled. Will the air reach the end of the coil? Or can air just loose pressure at a certain point? Thanks!

Hey guys I know that a laser can ionize air so that you could run current through air. I was wondering if anyone could tell me just how powerful (watts) the laser would have to be If I wanted to connect 2 point that are about 100 feet apart? 2 points have very low current but do have high...

Hallo, Working on building a cloud chamber based on thermoelectric coolers rather than dry ice or other "consumable" cooling methods, and having some difficulty working out some of the numbers. Say I have a volume of air at room temperature, for arguments sake 1600cm³, and I want to cool this...

I am trying to calculate the force that compressed air has on a cylinder. These cylinders are pushed in a production line for transportation using air. I would like to calculate the force such air puts on the cylinder. I have the velocity of the air, the área of the cylinder. Will using the...

Homework Statement The horizontal pipe is very large and long: 100 feet in diameter and 1500 feet long with an infinite supply of air on both ends. The pressure difference between the two ends is 0.6 psi. I assume friction is near zero as the pipe is so big so I ignore it. What is the...

Is it theoretically possible to get a round bullet to rise if shot horizontally provided the bullet ( projectile) is given "under spin"?

Hi, Could you explain the reason why the velocity varies in the wake region behind the cylinder in "flow over a circular cylinder"? the velocity variation is, minimum at a point parallel to the centre point of the cylinder and increases to free stream velocity as the vertical distance increases...

1. A ball is thrown vertically upward with an initial velocity of 27.0 m/s. Neglecting air resistance, how long is the ball in the air?Homework Equations vf (v final) = v0 (v initial) + at[/B]The Attempt at a Solution I set final velocity equal 0. So.. 0 = 27.0 m/s (initial velocity) +...

I have an air leak somewhere in a coil or 20 feet of pipe in a mechanical room next to a transformer. I have 160 psi of air on the system and it dropped 30 psi in two days. I have tried to find the lead with 60 psi of water currently but no success. I do not want to put a lot of water...

MODERATOR NOTE: THIS THREAD WAS ORIGINALLY POSTED SOMEWHERE ELSE, SO THERE IS NO TEMPLATE. Dear! I have a problem with one, complex exercise. I’ve divided it into three parts just to simplify finding the answer. So let’s start. The air is sucked from the atmosphere by a compressor. Atmospheric...

If I turn on a standing fan in my room how does the speed of sound change in the fast moving air compared to the still air around it? Would it be relatively faster, slower, or does it depend on the direction in which the fan is blowing?

Homework Statement Air at pressure 20[atm] enters an air machine and leaves at 1[atm]. what must be the temperature of the air at the entrance so that when it leaves it is 00C. Assume adiabatic process. Homework Equations PV=nRT Adiabatic: ##P_1V_1^\gamma=P_2V_2^\gamma## The Attempt at a...

I want to calculate the change of state for N2 and dry air at pressures above 200 bar with a max of 300 bar. Ideal gas law is not applicable at these pressures, but looking at real gas models there are several to choose from, among others: Van der Waals Redlich-Kwong Virial Bender Can someone...

Homework Statement At the start of the compression stroke, the cylinder in a diesel motor contains 300[cm3] of air at atmospheric pressure and 270C, and at the end of the stroke the volume is 20[cm3] and manometric pressure 41[atm]. What is the temperature. Homework Equations...

I am looking to open a series of valves in a chamber under 10" of lift(water) ~.36psi which are normally held closed by a very light spring and the constant air pressure. The valves are very light weight and range in surface size from approx 2 to 6 sq inches, or approx .72 to 2.16 lb of initial...

There is a metal cube that is any size desired. the contents of the cube is a vacuum of space. there is a tube that is also a vacuum of space that also can be any size desired. The third item is a ball that fits air tight in the tube perfectly at the furthest point from the ball. The ball can...

When calculating the cooling load of a lab,when i put 100% outside air in the ventilation section,the loads seem to leap extremely high (more than 4 RT above what it would be in a normal situation).I understand that the high volumes of unconditioned air would increase the load significantly.The...

Homework Statement A cylindrical pump of length 25[cm] pumps air in atmoshpheric pressure ant temp 270C into a big tank. the manometric pressure in the tank is 4[atm]. at which distance will the air start entering the tank. Homework Equations In adiabatic process...

I wonder if someone can help settle a debate I am having over using air compressors to aerate garden koi ponds? A typical pond will have a small electric air pump (44W rated, delivers say 50 litres a minute at 1.5 metres deep in a 10000L pond) blowing air through a diffuser to add oxygen and...

Homework Statement A cylinder of height 1[m] has a weightless piston on it's head. mercury is spilled slowly on the piston and it goes in. at what distance will the mercury start to spill over the cylinder. the process is at constant temperature. Homework Equations $$PV=nRT$$ At constant...

Homework Statement Car mechanics use compressed air tools to open bolts. Instead of using an air compressor one can also use a tank of pressurized air. There is an air tank with a volume of 50 L to work with. The pressure of the tank is 50 bars when it is stored indoors at 20 °C. The bolt...

Dear all ! I am an engineer from Vietnam! I just started to work 4 months ago. Now I got assignments with compressed air system! The compressor is not mentioned here! We have an air vessel of 500 Liters, and pressure is 7 bar. Before air vessel is an air booster with inlet pressure of 6 bar. The...

http://www.stuff.co.nz/world/asia/64507189/air-asia-flight-from-indonesia-to-singapore-vanishes If it lost contact at 11.17am NZT, and it is now 6.12pm NZT, that is way over six hours that it has been missing.

Hello All. This is my first post, and I hope it is not too simplistic, but I am out of my normal line of work here. I am trying to understand the relationships between flow, velocity, and cross sectional area with gases and fluids(air and water). Imagine a large vertical, cylindrical tank...

Is there such thing as a turbine that increases air speed/compression? This seems like a dumb question but I'm having a heck of a time locating any information on it because any iteration of "air turbine" entered into Google just brings up information about wind mills. I'm looking for something...

Hello! I have a problem with determining speed of sound basing on a data from laboratory. 1. Homework Statement I have to determine speed of sound by measuring the shift of time in microphone compared to speaker. The distance between them is constant and I'm changing the frequency in...

Hi, Would it be possible to hold electrified liquids in the air? There is an external electric field applied to the liquids. What kind of liquid must it be? I guess water wouldn't do the job.

Hi, guys! :) I do hope I am posting on the right thread here. So anyways, I'm looking into a certain topic: "Speed of Sound in Air as a Function of Temperature". Any thoughts on how I could do this experimentally? Warm regards, Paulene :)

Hello, I searched as best I could but could not find a direct answer to my question; I've seen similar questions but without the required data to be able to make the calculation. I thought this would be a simple calculation to find but apparently not. Compressed air source is 4.46cfm @ 93psi -...

I recently shifted to South Korea to pursue higher studies and stay with my sister and niece . My niece is working on a high school project on air pollution and indoor air quality studies . Starting with a write up on air pollution and then indoor air quality and effects on health and the...

Hi, Am I correct in thinking that for a medium such as air, the dielectric strength is a property of the material and as such has a single value for that material? The reason I ask is because I have been testing the breakdown of air between different types of electrodes and because the...

Hi! I have a question. The experiment goes like this. i hermetically close air and chloroform at standard pressure. now i want to calculate the end pressure of gas mixture after chloroform vapor gets saturated. is it as simple as adding up the chloroform saturated pressure to the starting air...

Hi all, Recently did a lab experiment where we had a nozzle pointing vertically upwards at a flat plate normal to the direction of the flow of air. The plate had a spring gauge on it so that the force of the air on the plate could be measured. The plate was moved to various distances above the...

At work we have a shed in full sun. Windows were cut in it to allow airflow. Louvers were installed to keep the rain out. However the sheet metal guys did a HUGE overkill on designing the louvers. I want to propose to my boss to remove half of the louvers so that we can get decent air flow...

Does anyone know what pressure air has to be compressed too so that the JT effect causes the air to liquify? I am running a simulation and I have the pressure up to 9000 psig and 0F and the drop in temp is only to -125F. The requisite temp to liquify air is ~ -320F from my simulation results...

Can you use a vacuum, or lighter than air gas within a tubular frame network to neutralize the apparent weight of the frame? If this is possible what is thee smallest possible size you could make this frame, I understand that the more you scale it up the lighter proportionately the frame would...

the barrel has a lid at the top...sealed. I make a hole at the bottom to attach water hose to it. Then I turn on the water hose. The water volume in the barrel increases, no doubt about that. When It takes 7/8 of the barrel. Will the air in the top 1/8 of the barrel be compressed? I ask because...

i have a pre made tank approx dimemsions 3x3x3 feet the thickness of tank walls appear to be 3/16 to 1/4 inch thick. with a 1foot square opening on top for filling this opening had a raised "wall" approx 2inches. tank is used to collect used oil for shop heating. (this tank looks like a...

In this clip the mythbusters are investigating projectile motion at a firing range: Using the fact that the bullet fell approximately 1 inch as it traveled 100 feet, I predicted it should travel 600 feet down the firing range before hitting the ground from a height of 36 inches. Instead, it...

What defines how much energy we could store in some gas by compressing it to a certain volume by applying a certain pressure? The compessability coefficient? Is there some gases which allow to store more energy than air? Which gas has the largest compressibility coefficient?

Homework Statement [/B] The shape of a car windshield is approximated in the figure below; its length is 2.0 ft and height is 1.5 ft. Obtain an equation of the windshield shape r as a function of θ, r(θ), in the polar coordinate system shown in the picture. When the car moves at 55 mph...

< Moderator Note -- thread moved from General Physics to Homework Help forum >[/color] If a ball is projected vertically upwards say with a velocity V. Case 1: Without air drag Case 2: With air drag What will be the difference in v-t graphs and the motion of the ball Air drag D=bv (b is a...

△Work = △KE + △PE Work = Force x Distance W=F△x Pressure = Force/Area W=PA△x Volume=Area x length W=PV Work = Pressure x Volume KE=(1/2)mv^2 Density = mass/volume mass = density x volume m=DV KE=(1/2)DVv^2 (work done by air pressure?) PE=mgy PE=DVgy (work done by gravity and air pressure??)...

How does weight affect air resistance? [i.e A heavy feather falling v.s a light one}Please be simple

Hi, everyone! I have a question: if we quickly fill a cylinder with steam from one end and with hot air from another end, both at atmospheric pressure and equal volume, with hot air 4 times hotter than steam, and then immediately seal that cylinder -- will pressure change as steam and hot air...

1. A parachutist of mass 62 kg is falling at 55 km/h when her parachute open. She then falls 24 m in the next 2.0 seconds. Find the force of air resistance acting on the parachute during those 2.0 seconds.2. Could I just find the force of friction?3. I found out what the force would be if not...

If you have a tank with compressed air. Say this tank is a cube of 1x1x1m. One of the walls are "mobile" but sealed so no air can excape. A spring on the outside is pushing on this wall so it will remain in its position at for example 10 bar pressure inside the tank. Now, atmospheric air has a...

I need create a math model to predict the temperature of a copper pipe with hot air flowing through based on the temperature of the air, properties of the air and copper, and the surface area of contact between the air and the pipe. The pipe will start cold but I will be looking to the...

Homework Statement What angles should an arrow be launched if it leaves the bow @ speed of 60 m/s and is trying to hit a target that is 150 m away? Assume target is same height as bow. Suppose the arrow is fired at an angle of 30 degrees & misses the target & hits the ground 1.8 m below from...