Thickness Definition and 328 Threads

an electron in a potential well of thickness (e.g 1nm) with infinitly high potential barriers. it is in the lowest possible energy state. to calculate the energy of the electron. i used: E=(n^2 pi^2 h(bar)^2)/ (2m Lz^2) which will result in approx 10E-19 j my question is, how can...

Hi. Situation: A pipe with a cut out so it will break when a shear force is exerted at the top of the pipe. The break point is at the cut out and the the force is impact in lbs. What is the wall thickness(or cross sectional area) at the cut out point? I know i may be missing variables...

Hi, I am hoping that someone could enlighten me about pipe schedules. I've searched online but there have been conflicting definitions for schedules, where some people refer to it as pressure and some referring to it as thickness. I need a pipe to be able to withstand 70bar of pressure...

Homework Statement Hi all, I was wondering if anyone can help with this? A uniform Steel strut (material Modulus of Elasticity 210 GN/m2, Poisson’s Ratio 0.3) of length 400mm and width 80 mm is restrained as appropriate at one end and under an axial tensile load of 20 KN applied to the...

hello everybody, I'm new here and i have this homework which i don't know how to solve it, please help me: Design the thickness of insulation for steam pipe of: -Pipe diameter 2 in. -Pipe length 200 m. -Saturated steam pressure 10 bar. -Ambient temperature 30°C. -Steam cost $4.5/MMbtu i...

Alright, chemistry student here. No previous experience with these types of problems. Doing an interdisciplinary student project where we have to insulate a thin aluminum wall. http://i.imgur.com/8ztNq.gif We have a x=5mm thin aluminium wall used for dividing two air flows. T1=308 K and...

Homework Statement What is the thinnest soap film (excluding the case of zero thickness) that appears black when illuminated with light with a wavelength of 520 ? The index of refraction of the film is 1.34, and there is air on both sides of the film. Homework Equations Im wondering do I...

Ok I am studying experimental physics and I wondering if you can determine the thickness of a target if you only know the area density. For example if you have a target of 70 micrograms/cm^2 can you determine the thickness from just this information ? I have tried to find equations but cannot...

Hi, how to calculate the limit of load you can place on the top of the circular plate with a quite big circular hole in it (OD 10 cm, ID 5 cm)? the question is how to calculate the thickness needed to bear 1 kg which is spread on the whole area (1 kg heavy object with the same shape as the...

1. given that the yield stress σy of the material is 475 Mpa, internal radius ri is 24.47mm, internal pressure pi is 6.07 Mpa, external pressure po is atmospheric, find the thickness required of the cylinder such that it does not undergo failure. (ro≥ r ≥ri)2. σr = [(pi ri^2 - po ro^2) / (ro^2 -...

Homework Statement You use exactly 3.0 gallons of paint to paint the walls of a room that measures 12 meters long by 12 meters wide by 8.0 meters high. How thick is the layer of paint that you put on the four walls? (No windows or doors) Use the conversion 1 gallon = 3.79 x 10-3m3. Homework...

Homework Statement I was asked to determin the film thickness for an oil film (n=1.33) for a light beam (500 nm) to give total reflection. I could calculate refraction angle for air to oil, but have no idea as to how to approach this question. Homework Equations The Attempt at a...

Hi guys, long time reader new poster. I am looking for ways to determine the thickness of some thin films of zinc oxide I have been producing. Conventionally I use SEM cross section, but the throughput of films has made this a little taxing. I've tried also weighing the substrates before...

a thin soap film is seen in sodium light by normal reflection method it appears totally dark deduce the possible values of film thickness given (myu)-refra.indx of liquid-1.333 and lambda wave.lgth-5893 angstrom

I am working on a hypersonic vehicle project and would like to calculate the boundary layer. The vehicle that I am studying is the Apollo re-entry capsule. I'm assuming a 2-D flow. Here's what I have done so far. Calculate the local surface inclination angle at any point on the blunt body...

Please I need help ASAP! This is the problem: Cowen cites the deposition rate of BIF in the Hamersley Basin of Australia as 30 million metric tonnes per year. He says the ore is 55% iron (volume); iron has a density of 8 g/cm^3. Assume the rest of the ore is made of silica, which has a density...

Hello I am currently building DIY solar panel.I have a problem regarding the build up of the panel. My question is can I attach the cells on to a normal transperant glass of about 5mm thick by a transperant silicon? My concern is if the cell will break or not, by the outer environment ...

Homework Statement Determine a)where the greatest stresses are b) overall change in length That is meant to be a hollow cylinder on the bottom section inbetween the dotted lines E = 200 GPa Homework Equations σ = Fn / A ε = dl / lo = σ / E The Attempt at a Solution The book gives the...

a certain bifringement material has indexes of refraction n1 and n2 for the two perpendicular components of linearly polarized light passing through it. the corresponding wavelengths are λ1=λ0/n1 and λ2=λ0/n2, where λ0 is wavelength in vacuum. If crystal is to function as a quarter-wave plate...

Homework Statement show that minimum thickness of quarter wave plate is d=\lambda0/4(n1-n2 Homework Equations \lambda1=\lambda0/n1 \lambda2=\lambda0/n2 The Attempt at a Solution for quater wave plates wavelengths must differ by 1/4 i can see its simple but i just can't see what...

How to calculate the minimum thickness of a duct which hold vacuum inside at 150 deg c? And what's the basic to select the stiffer size and distance between each stiffener. Thanks.

I need find the thickness of a piece of paper based on the known linear speed of the paper coming off the roll and the change in diameter of the roll. I have the ability to see the linear speed. It is consistant but changes from roll to roll. I know the starting radius, instantaneous radius...

Is there a general formula to measure the amount of heat lost per second (Joules per second) given the surface area which the water covers and the width of the insulator material surrounding it?

In most of the brane world models: our world is supposed to be an infinite thick mathematical surface in the higher dimensional world. Which is very curious. Are there any model in which the thickness of the "surface" is finite? Please, could anyone submit a good paper to me in this topic?

I noticed recently that hot chocolate when left on the table for a while and starts cooling at room temperature, starts getting thicker (more viscous). However, when it was put in the fridge overnight and got completely cold it became more liquid (less viscous). Why does this happen? Can someone...

We have a situation where we have air in front of the dry pigs and need to control the pig speed Medium is air, pressure is 17 barg upstream and 0.2 barg downstream and pig speed target is O.5 m/s for the pig in the 48" pipeline with a pressure of 17 barg. need to find the following...

Homework Statement An infinite sheet of copper conductor, thickness t, lies in the xz-plane. The sides of the sheet intersect the y-axis at y=\pm\frac{t}{2}. The current density in the sheet is given by: {\bf{j}}({\bf{r}}) = \begin{cases} j_0\left(\frac{y}{t}\right)^2{\bf{\hat{x}}}, &...

Hello Forum, the formula for skin depth is both inversely proportional to conductivity and frequency omega. There seem to be 3 cases when the skin depth of a metal is exactly (or tends to) zero: 1) if an EM wave of frequency f (any frequency) is incident on a perfect metal wall (infinite...

Hi, I am trying to obtain a relation for calculating the deflection of a parabolic plate of thickness (say 't') clamped at one end, with a concentrated load along the center line at the "apex" end. Any direct links for the formula? Thanks!

Homework Statement A soap bubble of refractive index 1.33 is illuminated by white light perpendicular to its surface and viewed normal to its surface. What is the minimum thickness of the bubble for which brightly-coloured reflected light would be seen?Homework Equations \lambda=4ntThe Attempt...

Shear stress of bolts Diameter of bolt Shear stress of plate Load carried Bearing stress of plate Bearing stress of bolts If someone could help me it would be fantastic Thanks

I read that the thickness of an ITO film affects performance as a trade off between transparency and conductivity. How thick can ITO be and still remain reasonably transparent to visible light? I found a couple papers which characterize the transmittance but only out to 500 nm or so. Could it...

Hey there I need to find the natural frequency of a Cantilever Beam. The beam is tapered in breadth, but has a uniform thickness. So basically the end goal is an equation for f as a function of the angle of the side cut. Clamped at one end L=constant B=changes though the length of the...

Homework Statement We have 5 cm of external diametre tubing with 200*C of superficial temperature. The boundary temperature is 20*C and the convective heat transfer coefficient is 3.0 W/m^2*C What is the heat loss Homework Equations q = U*A*(T1-T2) 1/U = 1/h1 + [r1 * ln...

Advice on working out the thickness of a "U" beam. First off hello all, seems a great forum and I look forward to posting up on here! I have an problem that needs some advice, I'm trying to work out the thickness of a U-beam. I have a few restriction on the dimensions of the U-beam, here are...

I want to design a welded structure steel stand to hold the weight of 600 pounds, by using 4X4 square tube. Please help me to find the thickness of steel tube.

Homework Statement A double convex lens has a diameter of 5 cm and zero thickness at its edges. A point object on an axis through the center of the lens produces a real image on the opposite side. Both object and image distances are 30 cm, measured from a plane bisecting the lens. The lens has...

Homework Statement How thick a concrete wall would be needed to give the same insulating value as 3.5 inches of fiberglass? Homework Equations Q = -A·k·ΔT/Δx k = -Q·Δx/A·ΔT The Attempt at a Solution So here, k is equal to the insulating value, and since I want the insulating value...

Hi, has anyone had any experience with visibility of single-layer flakes of graphene on substrates with non-optimum thickness of SiO2? We've been shopping for some Silicon wafers with 300 nm of SiO2, but our supplier can only ensure the oxide thickness within 10% of the specified value. I...

Homework Statement [PLAIN]http://img714.imageshack.us/img714/7747/43416215.jpg The attempt at a solution I have already solved parts (a) and (b). It's part (c) that I can't get. To get a minimum thickness at 50 MPa, I thought that the hoop stress equation would govern. Here is my...

Hello there, I'm an undergrad in my 3rd year and I'm doing an investigation into the 'Preparation of Thin Films and their use in Hall Effect measurements.' We are making thin films of bismuth on glass (with pre drilled terminals) in a vacuum system. The way they suggest measuring the...

Hello all, I am somewhat confused in understanding the depletion region of a p-n junction diode.Everywhere a depletion region is defined as a region near the p-n junction which is devoid of charge carriers.And the formation of this region is said is explain that it is due to the diffusion of...

I'm having trouble with understanding how to calculate a wall thickness change in a hollow cylinder unde axial loading. The length, outside diameter and initial wall thickness are given as well as the size of the load, Young's modulus and Poisson's ratio. I guess this isn't really a hard...

Homework Statement An infinite slab of charge with thickness d (from x=0 to x=d) in the x direction has a charge density corrosponding to rho (x) = Ax+B where A and B are positive consants. Find the electric field at point x1<d Homework Equations I know i have to find some guassian...

Yes, first to say that this's really a basic matter but I've found all around a week & still facing difficulty, hope someone has patient to help me an answer then i can go further myself :wink: As in the attached picture, a few ones have done their calculations & showed the different wall...

How would the whiteness of snow appear if Earth's atmosphere were several times thicker? I think it would appear red as most of the blue frequency light would be scattered before reaching the Earth and the majority of light being reflected of the snow would be red. Am i right?

I'm working on some stress analysis for work. I'm analyzing the design of a plate, part of which is meant to deflect under a load. Due to this sheet metal plate being somewhat non-straight forward geometry, calculating correctly is a bit tricky. I'm putting an undercut into the plate to allow...

Hello I have done some lab work where I have coated a wire with an organic layer. The density of the organic layer is 800kg/m^3 and the density of the wire is 2620kg/m^3. I assume 1wt% of the wire is the organic layer the rest is the wire. The mass of the wire with organic layer is...

Currently in our lab we have a WEDGE shaped sample that we would like to be able to know the thickness at various points along it. Our sample is about 5mm x 5mm. The wedge SHOULD extend from one side to the other. At the highest point, the wedge is 50nm, and then drops down, hopefully at a...

ok guys, suppose i wanted to build a round 8m diameter 1m high pool out of galvanized steel sheet. I will be filling it 0.7m with water. I am aiming to reduce its cost so I am calculating the thinnest sheet i am allowed to use without it failing. I will be using 7 sheets bolted together(each...