Tube Definition and 829 Threads

Fluorescent lamps work by ionizing mercury vapor in a glass tube. So now mercury atom has electrons in the lowest energy level K and there can be maximum 2 electrons in this shell. Now when you turn on the light the electrons in the ground state i.e K shell get excited and move to the next...

case 1)The hole is drilled before the liquid rises case 2) the hole is drilled after the liquid rises

Need help with an application I am thinking of. In this application just 10 cubic inches per second of cold air is needed, that too for 2-5 seconds only. Also, not a lot of cooling/heating capacity is needed, just 30C of air cooling should be sufficient. How would we construct such a device? I...

Ignoring drag, terminal velocity and friction, input 1143 seconds here: http://keisan.casio.com/exec/system/1224835316 It yields a velocity of 11.2 km/s (Earth's Escape Velocity) at freefall from a height of 6.4 km (a fraction of the height/depth of Everest, Antarctic ice cap and deepest oceanic...

Greetings, may I ask for a bit of help with a steel fabrication project? Pictured below is my design for a trailer-hitch mount to be used with a Harbor Freight tire changing tool. I need help determining the thickness and composition of the tube and plate steel to be used in the project. I...

Hello, Stupid computer scientist student speaking here. I am looking to heat a few inch long glass tube with a OD of around 10mm and wall around 1.5mm wrapped in Nichrome wire to around 365F. Air will then be drawn through the tube to heat up herbs sitting about the glass tube. (vaporizer) I...

Homework Statement Consider a evacuated long metal tube of length 'l' and diameter 'd' containing a metal source at one end. The metal source is connected to an oven and emits gaseous metal atoms in all possible directions. If an atom hits the walls of the tube, it will get stuck and will not...

Why is the central electrode in a Geiger-Muller tube always positive (and not negative)? Many thanks!

Hi, Please could you explain the difference between a subsonic Pitot tube and supersonic one Thanks

Homework Statement If there is a horizontal tube rotating on axis in horizontal plane. it is filled with an ideal gas , So which end will the pressure be higher ? the end on axis?? or the free end Homework Equations P.A= m .w^2 .r The Attempt at a Solution i think the free end should have...

Homework Statement An inverted U-tube monometer, as shown in Figure attached , has air at the top of the tube. If the pipes contain oil (s.g. = 0.9), h1= 0.6 m, h2= 1.8 m and h= 0.45 m, determine the difference in pressure between point B and point A. Homework EquationsThe Attempt at a Solution...

1. So, during one of my classes, the teacher showed us a small experiment, and asked us to explain how it works. The experimented consisted of a tube, closed on both ends, and attached to said tube is what I think is a magnet. Now, everytime he rotated the tube, the magnet rised to the top with...

Hey everyone, I'm building my first evacuated tube solar oven and I seem to run into a problem I can't get around. First of all, I am going to use half inch type K copper pipes with water as a heat transfer fluid. I am putting a vacuum (100 mbar or so) on the tubes to lower the boiling point...

Homework Statement A tone with frequency 2,00 * 10^3 Hz is held above a tube filled with water. The water level is increased and decreased. When the water level is 5.7cm below the opening of the tube, the first sound maxima is heard. When the water level is 39.3cm below the opening of the...

if you have a reference for someone with a semester of thermo (as opposed to a grad student with 3 semesters), a link would be appreciated . meanwhile, a quick question: temperature, as determined by one of its factors for gases, translational kinetic energy, follows a Planck distribution. but...

Ok, first off I need to explain my project first. I have a wood pellet stove that I want to use to heat hot water for a radiant heating system. I will have to do a custom job because nobody makes a kit for my particular stove. My question is howong of a colper tube is needed to heat the well...

Designing mechanical system where two concentric tubes will pass through high density membrane. Outer tube will have tapered end .Outer tube will have ultra thin walls (about 0.3-0.5 mm) .Inner tube is more rigid and will fill all space inside outer tube,decreasing chance for deformation of...

Hi guys, Bit of a noob engineer here so looking for some guidance. I'm designing a fixture which will be constructed from stainless steel rectangular tube as shown in the diagram. If I apply a 10,000kg weight over a 100mx100mm area how do I go about calculating the stress and ultimately safe...

I don't know a lot about classical physics but I was wondering how many volts a cathode ray tube emits?

Hi anyone have the procedure to design the plate fin tube heat exchanger (air cooler) at defined mass flow rates and inlet / outlet temperatures , or anyone have an software package can be used for this purpose , please can share it with me

I have a setup where there is a source of air pressure, a tube through which the air flows, a connector through which air flows, and a flow meter which reads the flowrate of the air at the end. The final goal is to use the readings from the flowmeter to determine the diameter of the tube through...

Homework Statement A venturi tube is a means of measuring fluid velocity. One particular device consists of a level, circular pipe of radius 5.7 cm which at one point narrows to a radius of 3.7 cm. An ideal, incompressible liquid flows through the tube and the pressure difference between the...

A horizontally oriented tube is rotating with angular velocity ω about one end of the tube which is open. The tube has ideal liquid filled inside it as shown in the attachment. Why does there have to be a pressure difference between two points in the ideal liquid at the same horizontal level...

Hello All, I would like to start learning how to ray trace but the tracing through a tube with a thickness of t has got me stumped. If I have an n1 (outside tube), n2 (Tube), and n3 (inside tube). n1≠n2≠n3. Knowing Θ1 (the angle of incidence in relation to the normal), I can calculate Θ2 from...

What happen when the capillary rise occur in a tube of insufficient length? My teacher told me that hR = constant where h is height and R is radius of sphere of which the curved surface of meniscus firm a part. She also told me that if h become less so R has to increase so radius of meniscus...

Hello, I am doing a project which involves very hot confined plasma. The problem is, quartz tubing is way too expensive for me. I don't want to deal with impurities so I came to ask if you can suggest any cheaper alternatives. Here are my ideas: Borosilicate glass with "getter" coating. (I...

I have a question which has intrigued me for quite some time. If the electrons are accelerated using a potential difference in a cathode ray tube, the electrons should get accelerated till the time they reach the anode only. Once they cross over (ie. move to the other side of the anode), they...

osmotic pressure is the pressure required to stop the flow of solvent molecules due to osmosis.So in case of U shaped tube as in the image below hydrostatic pressure is the pressure which will stop the flow of solvent molecules due to osmosis. So hydrostatic pressure =osmotic pressure...

Homework Statement The tube weighs 100[kg], is 1.2[m] high with radius 0.4[m] and is on a rough surface. a force is applied at the top. the first question was what's the magnitude to turn over the tube, but the second was what's the minimal force needed to do that. Homework Equations Moment...

Homework Statement Two smooth balls of radius 10[cm] and weight 6[kg] are inside a tube of radius 16[cm] that's on the table. what are the reactions from the walls and what is the minimum mass of the tube to be in equilibrium Homework Equations Disassembling of forces using trigonometry The...

Homework Statement How does fluid move from low pressure area in a Venturi to a high pressure area, which is downstream from the Venturi. Homework EquationsThe Attempt at a Solution Not understanding the mechanism here, as I thought fluids only go from high pressure to low presure. Since the...

I am working on a problem in which viscous flow comes out from an inclined tube, forming some kind of a fountain. In the tube the fluid is Newtonian and the flow can be treated as Poiseuille flow. I want to study the movement of the fluid after it leaves the tube. Can someone point me about the...

Hello all! I am not the most well versed in engineering but my old man is attempting to build a slide out rail system for his pick up truck. The design we have in mind calls for a frame made of tube steel however what we have laying around the shop seems to be a bit overkill (or maybe not). The...

What factors determine the anode plate-to-grid capacitance? I know that the capacitance of a regular capacitor is determined by the surface area of the plates and is inversely proportional to the distance between them. Does this hold for vacuum tube grids and anode plates? The reason I'm asking...

Hi, I'm a mechatronics student and I am currently working on a project on the effectiveness of a vortex tube to cool a cabinet. The cabinet has a thermostat inside and if the temperature exceeds a threshold, an air compressor is turned on, causing the vortex tube to cool the cabinet. The cabinet...

I need to make a steel beam ( or aluminum) of square tube ( box beam) 10 feet long with a balance point 2 feet from one end. The short end will have 60 lbs on it and the long end will have 30 lbs. how thick of a wall will the square tube need to be to hold the static load?

Homework Statement We have a tube with the top end open and the bottom end closed. There is some oxygen gas in the tube and on top of the oxygen there is 10 cm high column of mercury. The initial temperature is 20oC. Then the tube is flipped over and heated to 40oC. The column of mercury shifts...

Is there some specification in manufacturer's literature or some standards about limit of fluid mixing/ seepage through tubesheet of any particular heat exchanger. Is this an important parameter of specification or it does not matter in every application. If such parameter exist, what is its...

Homework Statement A capacitor made of a round solid bar and a thin round tube are coaxial, they are very long. the radii of the bar is ra and of the tube rb. they are both charged with λ, the charge per unit length, with opposite charges. what is the potential difference. Homework Equations...

Hi everyone, I'm doing a simulation and need some help. A capillary which is closed on both ends with the length l (x=0 to x=l), with a radius R and the volume pi*R^2*l is dropped on a parachut at the time t=0 from a hight h above ground. At t=0 the pressure inside the capillary is p_i0 (this...

Problem Statement Two identical spheres of radius r are placed inside a cylinder of radius R as shown in the diagram below. You are given that R/2 < r < R and that each ball has a weight W. All surfaces are smooth. Show that there is a minimum mass, m, of the cylinder which will allow it to...

How does passing mercury, salt water, etc thought a copper tube create electricity? and dose it create a magnetic field?

I am trying to complete a project and have to properly size some steel tubing. The project is a belay bar for a slackline we have in the yard. I have 2 poles that are set in the ground 21' apart and a slackline runs between them. We want to run a steel tube beam, permanently attached to the...

How to derive the formula to find the bending stiffness of an isotropic tapered tube which is cantilevered with a point load applied at the free end?

Difference between neural tube and dorsal nerve cord?

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 have made a pitot tube that I am using to measure the velocity of air in a pipe. First, I placed the probe into the pipe such that the hole in the probe was parallel to the flow to obtain static pressure. It did this successfully and I proved this using a piezometer. However, I then turned the...

Homework Statement given mass: 100g(the one hanging) Q1 = -30(mu)C Q2 = 70(mu)C Q3 = 50 (mu)C T=? Length of tube = 2m Length of rope = 1m Homework Equations Ft + Fg + Felect =0 F =k *q1*q3/d2The Attempt at a Solution Those were the equations I have done so far, so the answer is 46N & the...

Homework Statement i have a project regarding to boiler efficiency and how can it varies with excess air and flue gas temperature ( using the indirect method ) i will estimate the boiler efficiency at a different conditions , it's not that i can't do the calculations but doing the same thing...

Dear experts, I´m trying to model in ANSYS Mechanical (v14.5) the linear buckling behavior of a cylinder made of BEAM4 elements under combined loading (axial compression and bending moment) applied at the ends. How should I set up the boundary conditions of a cylinder to keep rigid the ends...