Air Definition and 1000 Threads

Summary:: Design compressed air energy storage for PV plant [Mentor Note -- Thread moved from a technical forum, so no Homework Template is shown] Hi All For a PV project of 5 kW, we will use a CAES. The preliminary design will consist of a compressor - 2 heat exchanger - Air receiver - air...

I suppose the trick in this question is to realize that the drag acts in opposite directions when the ball ascends and descends and that the ball actually takes less time to rise and more time to fall than normally. I make a small sketch of the problem alongside. Attempt : The total time of...

Hi, I'm struggling to start this exercice, where I have an inclined air hockey table with an angle alpha. They gave me this chronophotography (this is online) saying that the ratio is 1:1 I really don't know how to proceed since this is online and I'm thinking if I measure this with a ruler...

Using the ideal gas equation ##PV = nRT\Rightarrow PV = \frac{m}{M} RT## where ##m,M## are the mass and molecular weights of the gas respectively. This yields ##\frac{m}{V} = \frac{PM}{RT} = \rho##, the density of the gas at a point with pressure ##P##. If only we can obtain the variation of...

In the movie The Abyss an oil rig crew works and lives at the bottom of the ocean in a deep sea structure. There is a compartment where there is an opening in the floor allowing the crew to lower a submersible craft without going through any kind of air locks etc. We all should know from high...

$$\rho_{Hg} gh_{actual} = \rho_{Hg} gh_{measured} + \rho_{air} gh_{air}$$ Note: by "actual", I mean "theoretical", i.e. what the barometer would measure were there no air inside it. By "measured" I mean "as measured by the faulty barometer, i.e. with some air introduced". I believe this...

Could air escaping through a narrow opening into a vacuum freeze due to cooling from Joule-Thomson expansion, and cause frozen N2/O2 to accumulate around the edges of the opening until it clogged shut ?

Can someone show or illustrate how purely algebraic physics can describe black holes, gravitational waves or other predictions of General Relativity? In a letter of Einstein to Paul Langevin, 3 October 1935, as translated in Stachel 1986, 379-80, he wrote: "In any case one does not have the...

In thinking about temperature stratification of air: I assume that in a truly closed system with no heat inputs, air would NOT stratify by temperature. On the other hand, a heat source introduced in a closed container would generate stratification while it was generating heat (and following for...

I am considering building this type of heat exchanger, as I have seen several youtube videos on the build. The inside tube is aluminum, I am planning on building one from the top of my roof to nearly the floor, so ill say 5 feet. I am thinking of using a 1.5" inch aluminum tube, and bringing in...

Could not find reason on molecular level. E.g. here some explanation "There are two reasons: at higher altitudes, there is less air pushing down from above, and gravity is weaker farther from Earth's center." However, when I start to imagine particles, when there are only a few I get opposite...

I have come up with the change in height as 170 cm. My professor does not want to solve for the problem for a reason I do not understand. 170 cm is not part of the answer key. The answer according to the answer key is 65 cm. My attempt is: Initial temperature: p=F/A; (50 *9.8) / (pi * 0.05^2)...

This is for a campervan project I am working on, I am trying to take outside air that is cold (Canadian winter) and mix it into the return air in my diesel heater. I need to hit a specific minimal CFM to maintain proper Co2 levels inside and I would like to be able to calculate this. The axial...

My goal is to determine the ideal amount of air flow, in order to keep CO2 below 1000ppm and to minimize heat loss. I calculated the following based off a similar post in this forum, and I am hoping this can be verified so I know that i am in the right ballpark and going in the right direction...

What would happen if you tried to fly through obstacles using warp drive? Distorting space so that two points are closer wouldn't get around the fact that there might be obstacles (e.g. air molecules, space dust, empire destroyers) that you would bump into along the way right. Would all of that...

I am doing a physics lab where we are supposed to calculate air resistance and find the impacts of velocity and cross sectional area on air resistance. For the experiment, we rolled a cart down a ramp and measured data using Pasco Capstone software. When rolling the cart down the ramp, we...

Speaking of the the oft-referenced adage 'Given sufficient (time akin to orders of mag greater than the age of the universe ) the probability of all air molecules randomly collecting on one side of a room, leaving the other in vacuum - while very remote - is not zero, .' Is this not actually...

Recently I saw an exercise on electromagnetics (plane waves) in which it was said that a plane wave was traveling through vacuum (ε0 and μ0) BUT with losses, i.e, σ ≠0. Is that possible? I think I have read in the past that it's OK in some texbook, but now, I have searched for it in a couple of...

I want to compare diffusion of a tracer gas with a low exposure limit (e.g. isoflurane) to the advection of air by a ventilation system. When will diffusion exceed advection? I can't make sense of diffusion constant to compare transfer rates or velocities. At room temperature the diffusion...

Both alpha and beta radiations can only travel short distances through air as they're not as penetrating as gamma radiations. How long gamma radiations with 22 MeV energy can travel in air? Is it meters, kilometers, miles, etc. Is there a difference between a lower energy gamma ray and a higher...

Hello, this is an assigment form the 4th grade high school physics in Croatia, concerning electromagnetic waves. Radio waves of wavelength 12m propagate from the source. The source is on the surface of the water and two waves propagate from it: one through the air and the other through the...

Total acceleration equaled = -9.81

Hello everybody! I was wondering today if physically, it'd be possible for the world to develop an air conditioner without an outdoor heat unit? I know this seems to violate the second law of thermodynamics, but the known version of the second law thermodynamics only consider this is impossible...

I want the board to use air to lift itself of with the coanda effect which is when air sticks at the bottom of somthing and proppels it upwards along with specially designed heliblades.l and I want somthing to cover tge blades and make it safe and I want it be compact like back invite future or...

Hi all, I've been trying to follow a question I came across on a website. And I'm able to understand everything up until the separation of variables for solving the differential equation and coming to a solution with arctan. But there are a few things that aren't explained that I was hoping...

This video talks about how air bearings can be made using porous materials like graphite. Is it possible to get a comparable performance using non-porous materials, with an array of pin holes? The video talks about how the carbon seat can be easily worked into conforming with the matching...

##4\pi\mathcal L = -\mathcal e \frac{\partial A_i }{\partial t} - \phi\mathcal E^i{}_{,i} -\frac{1}{2}N\gamma^{\frac{1}{2}}g_{ij}(\mathcal E^i \mathcal E^j +\mathcal B^i\mathcal B^j) +N^i [ijk]\mathcal E^i\mathcal B^j## MTW (21.100) I'm trying to produce the result required by the problem...

I hope you guys don't mind a bizarre question from a novice. I've learned just enough about fluid dynamics to be dangerous. Assume that we have a straight, rigid tube with a constant inner diameter. It's not long, let's say it's around a foot (in case that matters). We cut a chunk out of the...

2 scenarios: 1) Situation in the movie "2012", where volume of ocean water hasn't changed, but worldwide seismic activity has caused massive tidal waves. In one scene, a ship is sailing by Mt. Everest close to its peak. In such a scenario, I believe the air density outside the ship would the...

Hi, I'm trying to solve this integral and then isolate V, but I can't get the right answer. I don't know where is my errors. I probably muffed the integral. ##-bv -cv² = m\frac {dv}{dt}## ## \int_0^t dt = - m \int_{Vo}^v \frac {dv}{bv+cv^2} ## I get this after the integration ##t =...

Hi, A quick question on a conundrum I seem to have encountered. My main question is: why is it wrong to use the formula above instead of the SFEE approach? My approach: Use the formula: $$ w = \frac{R}{1-n} (T_2 - T_1) $$ From the data book, ## R = 0.287 ## kJ/kg K and ## n = \gamma = 1.4 ##...

Please advise for cooling time on air conditioning. I have a project and customer asked me to make a comparison between their requirement and my proposal. And here's the result. Let's say that we provide a room with same capacity as above, function, delta T, load on that room, but ONLY air...

I'm a parent and have no idea, just looking for help please

Hi guys, I used to post on here quite a bit back in 2005-2007 when I was studying Physics in school, I remember it always being a great resource so hopefully I can get some similar help with this "real life" problem I'm having now! We are having a mini-heatwave here in the UK the last few...

I am trying to understand an excerpt from an article describing the vibrations of a string (eg. guitar/piano) which reads as follows: This is basically the wave equation with Δm representing a small piece of mass from an interval of the string and two forces added to the right side. He...

I've just purchased a book of child scientific experiments and it has an experiment that is titled 'Weigh some air'. It shows that if you make a scales with a piece of wood and a pivot and then balance two empty balloons on a either end and then fill one of the balloons with air the scales will...

I am open to ideas of a way to test a bus bar for insulation flaws that has a 3D shape that varies in a production environment. I have a DC bus bar that when it was just straight we would run a high potential test on a metal table that is the reference plane, and then flip it over to test the...

I used the form of the mean free path equation taking advantage of the fact that the Boltzmann constant is equal to the ideal gas constant R divided by Avogadro's number, because I didn't know if I could use the Boltzmann constant in the ##1.381\cdot 10^{-23}J/(molecules\cdot K)## form...

good day! I did not find a suitable forum thread, so I am writing here ... There is a valve through which you need to drive gas under a certain pressure, physically there is no way to drive gas, so it was decided to replace the gas with air. Knowing the required pressure and gas temperature, how...

I'm struggling with explanation of part 3. I don't know why they are using adiabatic equation while the gas is constantly heated by condensating vapour. While we are deriving adiabatic equation we use the fact, that there is no additional heat put into the system. Thank you in advance.

To reduce the transmission of coronavirus, people are recommended to stay 6 feet apart from others. The 6 feet number is a simple guideline, but there is not much difference between 5.9 and 6.0 feet. How does the number of droplets you breathe from another person vary with the distance d? Is it...

I am going to be working on some calculations for an air surge tank to minimize fluctuations downstream of the tank in an engin'e intake syste, Any suggestions/sources where I could study for this? Thank you!

The Blackbird wind powered car travels directly downwind faster than the wind speed powering it. Typically a 10 mph wind from directly behind it will cause it to travel at about 30mph. I am trying to analyse how the car accelerates from rest. I know how it travels faster than the wind speed so...

Hi, I am looking for some guidance on how to approach this calculation. I have an air cylinder operating a lever assembly that then applies pressure to a pulley of which a belt is wrapped around. I need the belt to have about 4500 lbs of tension. How do I work backwards to figure the required...

Hey, first post here. So I have to classify these 6 elements under closed-loop/open-loop system and under CO2 removal/oxygen supply. I thought it should be: Closed-loop CO2 removal: Rapid cycling anime, Lithium granules Closed-loop oxygen supply: Water electrolysis, Cryogenic tanks Open-loop CO2...

I have a problem. The task is to develop an differential equation of the airflow of a balloon. I know that it is dependent on the volume and pressure. But I can't get a good differential equasion. Can someone help me? [Thread moved from the technical forums, so no Homework Help Template is shown]

Hello! I'm brand new to the physics forum so please excuse any mistakes I make. I'm not even sure if I'm in the right forum section lol. My goal is to create a air cannon to launch a piece of dog food (super overkill) and I have pretty much 0 background in anything post-high school physics. I'm...

What forces act at air particle at curved streamline, looking from inertial and non-inertial frame of reference? (show free body diagram)

unsure

2500 N [south] + 3200 N [south] = 5700 N [south] 5700 N [south] - 6000 N [north] = 300[north]