Air Definition and 1000 Threads

Hello all, this is my first post here, so please excuse me if there are any mistakes or important information is left omitted. Now, my problem is quite intricate and specific so I will be thankful for any information I can get. Using Excel, I am looking to model the volume flow of air through...

I'm working on a kinda-sorta confidential device. I would like to know how much psi is required to lift approx. 400 pounds 120m (about 393ft and 8 13/32 inches) into the air. The thing I'm working on is still in the designing stage, so don't worry about the specifics of individual thrusters and...

Homework Statement A hot-air balloon has a volume of 2000 m^3 and generates a lift of 2720 N (assume the outside temperature is 20◦C with an air density of 1.2 kg/m^3). A)What is the density of the air inside the balloon? B)How many moles of air are inside of the balloon (the molecular mass of...

Hi, I am wondering if anyone can help me out with this, I'm looking to create 130.5 PSI of Water pressure for 15-20 seconds. If I were to pressurize an air chamber what size/volume would be required to achieve the above? Or would it be better to directly pressurize a chamber with water...

I was hoping to find out how long it takes for 1000 ml water to heat up to air surrounding air temperature - is there a general equation that can be used to work this out? For example, 1000 ml of water = 14 deg C; surrounding air temperature = 18 deg C. In more detail the water container volume...

We have a solid cube with some mass that we fire as a projectile at some angle. The cube is launched in such a way that two of the faces are perpendicular to the initial velocity vector. Assuming there is air resistance, would the cube change its orientation while it flies, even if the mass is...

Homework Statement Part A: Calculate how many mocules per cubic metre in air at 27°C and at a pressure of 1.1 atm (1atm is 1.01 x 10^5) Part B: What is mass in grams of 2.4m^3 of this air. Assume that 75% of the air is N2 (with molar mass of 28 g/mol) and 25% O2 (with molar mass of 32 g/mol)...

Homework Statement An Astronaut on a spacewalk has an oxygen tank strapped to his suit. The oxygen in it is pressurised to 5 atmospheres (5x10^5 Pa), and the volume of the tank is 15 litres. a) The oxygen is pumped to his mouth at atmospheric pressure (1x10^5 Pa). What is the maximum volume of...

I need help with ideas on how to pump water our of a sump pump that is always filling up. Using a sump pump when the float is tripped is really load. I need something that quietly pumps the water out steadily while not using up huge power...but it needs to be quiet! I see these aquarium...

Homework Statement measure the velocity of sound in the air using tuning fork and a pipe closed at one end method a: End Correction involves applying a correction factor to the first resonant length based on the diameter of the tube used. method b: Second Resonant Length involves finding two...

Hello,just seeing if someone can help me on here,i have a rc glider measuring 2200 mm on the ground,when in the air it measures about 35mm. Can the the height be calculated from these measurements.

I've been trying to figure out this problem for hours my whole group and most of the class is stumped. We understand that we need to relate the equations of F=ma, Fd = (Cd*p*v^2*A)/2, Fnet=Fd-Fg. No data is given. The answer is a V=____ equation. Even just an answer to #1 would be very helpful...

Is there a formula covering this? (not including free fall/gravity) I have the drag coefficient, velocity and every other variable I think I would need for the object in particular.

An object with a mass if falling with a force that is equal to its own weight of 25 pounds. The air resistance causes a decelerate force equal to 1/2 the velocity of the object at any time. If the object falls from rest, what is the velocity of the object after 8 seconds? I'm just confused at...

Hello- First post here, I can't seem to wrap my head around this concept and how to overcome it. I read here: https://www.physicsforums.com/threads/air-lock-concept.83124/ that air's compressibility is what stops flow, why is this? I also read that a stronger pump (in a vehicle's fuel system...

Hello, I do not really know if this is the right place to post this message ... if it's not then I'm sorry I am looking for a valve that allows the flow of liquid but prevent air escaping out form let's say a sealed container ... Is there such a thing?

Air pressure decreases at a rate of 2.5 pascals per kilometer in the eastward direction. In addition, the air pressure is increasing at a constant rate with respect to time everywhere. A ship sailing eastward at 10 km/hour past an island takes barometer readings and records a pressure drop of 30...

This was an extra question in an exam I took today. The temperature of the air in the bottle remains constant. I know this has something to do with buoyancy and ideal gases since temperature was mentioned in the question, and I think I could have easily solved the question, had the submerged...

A water skier of mass m is pulled at a constant velocity v by a boat of mass M. Tension in the rope held horizontally by the skier is T. a) Find the total resistive force by the water and air on the skier. b) How much upward force does the water exert on the skier?What equation would I use to...

Homework Statement Neglecting air resistance, if you throw a ball straight up with a speed of 20 m/s, how far will it be moving when you catch it? Homework Equations None The Attempt at a Solution

If I took a hammer to each of the screens, which would crack first with a minimum amount of force? If I put a screen protector on it, would it change the answer of which one would crack first? I tried to pick two models which had similar frames. If the using different models actually makes it a...

I am trying to size an orifice to place on an outlet of an air vent line. The reason for this is that I am installing a noise suppressing muffler, but it is only rated for 300 psig. Since I am venting a line that will be pressurized to 1600 psig, I'd like an orifice restrictor in order to...

hello. I have to design and test a gas turbine that uses pressurised air as a project. however the problem is, I don't know where to start. can anyone please help me? do I start with the blades or the housing? I have seen some videos on youtube, but this is a university project and I think its...

Homework Statement Two students conduct physics experiments on a balcony 19.6 m above the street. One student throws a ball vertically downward at 14.7 m/s. At the same instant the second student throws a ball vertically upward at the sam speed. The second ball follows the same path as the...

Homework Statement Assuming normal pressure and temperature outside, and normal pressure inside, what should be the inside temperature (in Celsius) if the hot air balloon has diameter 17 meters and carries 446.3 kg load? (Except the mass of air inside, everything else is included in the...

Homework Statement A helicopter is hovering 10m above the ground, weighs 6230kg and the rotors are 14,6m in diameter. Which speed does the air have that the rotors are pushing down? The Attempt at a Solution i really have no idea where to begin but the chapter has to do with impulse so i...

i am doing a research about ionized air ,and i have little question how much electrical resistance ionized air have?

Hello, I apologize in advance if this is the wrong section, it seemed the most appropriate Dolphins are able to produce rings of air which seem to counteract buoyancy by rotating ( I'm assuming rotation ) https://www.youtube.com/watch?v=bT-fctr32pE How and why is this true ? Thanks

If fan blades move in a circular way how is the air moving towards you (in front of fan) ? Also propeller and fan have different shapes, does it mean they work different?

Let's say that I have a stick with weight evenly distributed throughout. I attach a fan to one end of the stick, then balance it from its new centre of mass. I measure the distance from the ground to the stick then drop it. The stick tilts up towards the side generating more air resistance (fan...

Folks, I have an application that will require an air inlet port to occasionally be exposed to water (splashing mostly), a simple splash guard will likely not work. Are there any off-the-shelf or simple solutions that anyone can think of that can be used for keeping the water from entering...

Homework Statement A puck of mass m is kicked up an incline (angle θ) with initial speed vo. Friction is not present, but air resistance has a magnitude of f(v) = cv2. Solve Newtons second law for the pucks velocity as a function of t on the upward journey. How long does the journey last...

I had an idea for a type of shoe similar yet different from air Nike, and I would appreciate some comments. A hind foot air chamber would be compressed upon a runners foot strike ( with a force up to three times body weight). The air would be pushed through a one way valve into a rigid mid...

I am designing an almond dehydrator as a part of my university project and need some advice regarding air flow in the dehydrator. There is a hollow perforated cylinder with a heating device in the middle. This cylinder is divided into two sections. The lower section has to take in cool air...

Homework Statement A hair dryer is basically a duct in which a few layers of electric resistors are placed. A small fan pulls the air in and forces it to flow over the resistors where it is heated. Air enters a 900-W hair dryer at 100 kPa and 25° C, and leaves at 50° C. The cross-sectional area...

Homework Statement please refer to the question, since at the positon Q , the lighr ray is blocked by the substance , (as in the diagram) , why the bright fringe is seen at Q , In my opinion , it it should be a dark fringe. whereas at P , the lighr ray is not blocked , so it should be bright...

Homework Statement A projectile that is subject to quadratic air resistance is thrown vertically up with initial speed v0. (a): Write down the equation of motion for the upward motion and solve it to give v as a function of t. (b): Show that the time to reach th top of the trajectory...

Homework Statement i can't understand why the optical path diffrence is 2nt+0.5λ. why is it so? the 0.5λ is due to the path difference change of 180 degree of when it is reflected lower ray when it is reflected from the lower glass surface... why there's also phase change of 2nt. since both...

I want to derive some equations for a 2-D airplane's motion, specifically when it lifts off and lands. Can someone show me where I can start and how I can use differential equations to develop equations like the speed/position of the airplane in its x and y components? Also, if anyone is...

After a science fair experiment we have measured the similarities and differences of plasma created by air and helium. Our methodology is as follows. Methodology A(air): 1. Light a match and place it on a small raised surface inside a microwave 2. Cover the match with a glass bowl/beaker...

I am having trouble wrapping my head around the idea of a piston/cylinder type arrangement where the piston has a small area around the outer circumference that would allow air to travel between the front and back of the piston. To clarify, imagine a completely sealed adiabatic cylindrical box...

Consider the following: I have 2 PVC pipes, one is small enough to fit into the other with a little extra space. A rubber ring is placed around the smaller one to fill up the empty space, making a good seal to push air in and out of the larger one. Ignore any friction caused by the ring on...

Okay, so I am looking at this article (link at bottom) and it says they have a microorganism liquid contained inside of a CLOSED steel pipe fitting and they heat it until it's reached about 570 degrees inside. SO HOW MUCH PRESSURE GROWS INSIDE THE CLOSED CONTAINER? As far as a real life...

Correct me if I'm wrong I'm only 15. But doesn't air pressure affect the speed at which is needed to make a crack/boom. If so it would be easier at 50k feet to go faster, but you would not created a cone until you reach a higher speed. And vice versa with say. 5k feet.

Homework Statement A tank containing air is stirred by a paddle wheel. The work input to the paddle wheel is 9000 kj and the heat transferred to the surroundings from the tank is 3000 kj. The external work done by the system is ? Homework Equations dU = Q-W The Attempt at a...

I am doing a research project about wind pressure and the different uses one can achieve by changing the pressure, volume and speed. I am comparing a hot air balloon ride vs an air plane vs human flight. I am looking and what minimum and maximum MPH is needed to achieve human flight and with...

When Stiochiometrically correct mixture(equivalence ratio=1) is burned in air fuel cycle some of the air is still left after point 3 in P-V diagram...Theoretically the whole fuel and air should combust till point 3..Then why is some air left out there.And thus the max temp is when mixture is 6%...

Working on a project where we have been asked to utilize waste heat from a combustion process in order to increase the temperature of oil in a separate process. The hot air from combustion is at 340C and the oil is at 22C with a target temperature of 65C I have not seen any hot air heat...

Hi can anyone point me in the direction, or tell me how you can calculate the energy content of air at a given volume and pressure? Let's say 1 bar and 1 litre. Also is there a calculation for working out the energy available in that figure to perform work? Thank you.

Homework Statement Model the trajectory of a projectile with an initial velocity v_0 that is subject to the force of drag.Homework Equations F_{\text{d}} = \frac{1}{2}C_{\text{d}}\rho\text{A}(v(t))^2 v_x(t) = v_{0x} + \int_{t_0}^t a_x(t')\mathrm{d}t' The Attempt at a Solution I really...