Beam Definition and 1000 Threads

Homework Statement A 5m metal beam is supported on 2 supports. The beam is 30kg and the man is 65kg. The man stands at A, to prevent the beam tipping extra weights have been placed at B. Find reaction forces and the weights that have been placed at B. Take acceleration due to gravity to be...

Hi, like the title says, how do we actually calculate when a cantilever beam fails in reality? We’ve been taught that these are absolutely fixed to the ground. However, in reality these would probably be bolted onto the ground, so how do we calculate the force trying to lift the fixed beam on...

1. What is the advantage of using class 2 laser light? I would really appreciate if reference source is also given!Homework Equations Not needed.[/B]The Attempt at a Solution Well, I thought that using monochromatic light would made it easier to measure the distance between fringes. And also...

Homework Statement A beam of neutrons (moving along the z-direction) consists of an incoherent superposition of two beams that were initially all polarized along the x- and y-direction, respectively. Using the Pauli spin matrices: \sigma_x = \begin{pmatrix} 0 & 1 \\ 1 & 0 \\...

Homework Statement A rigid beam with a length of 4.00 m has a mass of 50.0 kg and a uniform mass distribution. It is supported at either end as seen in the figure by resting on the supports, but is not attached to them. If you call the support on the right support 2 and the support on the left...

Please see my attachment of a recent observation of light traveling through a medium. There is no source, just my observation The packets of light appear to be visible, distinct , moving at different speeds, and display the various colours for each wavelength. Is this normal / possible in a...

Homework Statement Beam spans 40 feet, with uniform loading of 500 pound/feet and a point load of 4000 pound at mid span. Support A is roller, support B is pin. How to determine the maximum moment and maximum deflection due to the loads. Use Force method Since it is a Determinate...

Homework Statement Homework Equations Beam problem Deflection Statically indeterminate The Attempt at a Solution Am I correct? Or should the assumed deflection at B be the difference in deflection between B and C? Thanks

If a beam is fixed at both end and subjected to nonuniform bending would the upper section of the beam still be in compression. My intuition and free body diagrams suggest it would but geometrically in this case, wouldn't all sections of the beam, even the upper section, have to elongate/curve...

Homework Statement Homework Equations Boundary condition EI(d^4y/dx^4)=w The Attempt at a Solution Boundary condition: At A, x=0, y=0, slope=0 At C, x=L/2, y=0, shear force = -Rb At B, x=L, y=0, moment = 0, shear force = 0 I know there are 2 distinctive formulae for A-C and C-B. For A-C...

Homework Statement if a beam fixed at two points is on an angle say 45 degrees from the x or y-axis instead of running parallel to x-axis in most questions does this effect calculations? The force acting upon it would be a load directly downwardsHomework Equations N/A The Attempt at a Solution...

My mechanics of materials book states that in order for an element to be in equilibrium it must have equal horizontal and vertical shear stresses. However, it also states "The shear stresses in the web of a wide-flange beam act only in the vertical direction and are larger than the stresses in...

Homework Statement "A beam of mass M = 280kg and length L = 2.2m is attached to a wall with a hinge (at a 90 degree angle to the wall, sticking out horizontally), and is supported at the other end by a wire making an angle of 30 degrees with the horizontal beam. What is the force acting on...

I am looking to build a 3 point hitch air seeder. My plan is to build it 20 feet long with the hitch in the middle. The openers will be a disc opener with a 450 lbs trip which I am planning to space them at 6 inches. As the openers are built to attach to a 4x4 box steel beam, I am wondering if...

Why cathode rays which consist of electron that do not have any colour are seen as a colourful ray of light in a discharge tube??

I'm having trouble understanding the phase shift produced by a beam splitter. I seem to be finding conflicting information. I'm specifically looking to understand a 50/50 beam splitter where one side has a dielectric mirror, as shown in this figure from wikipedia: I understand the pi...

Homework Statement Mohrs circle question - https://imgur.com/SKeTUXN Shear stress in I beam question - https://imgur.com/34yTyCAHomework Equations Mohrs Circle - None Shear stress in I beam - I = d . b^3 / 12 tmax = (F / I . b) . (A1 . y1) + (A2 . y2)The Attempt at a Solution For the...

(sorry if posting in the wrong place) I am looking for some mirror setup where rotation one or more elements in the mirror setup will allow to shift the beam along its axis. Two mirrors in a galvanometer scanner type setup work well for controlling the angle of the beam. Rotating risley...

Homework Statement Homework Equations In my attempt at a solution The Attempt at a Solution

Homework Statement I've been trying to find the unknown forces for this beam so I can complete an FEA analysis. Homework Equations ∑mz=0, ∑fx=0,∑fy=0 The Attempt at a Solution Attempt is attached

Homework Statement See attached photo Homework Equations Stress = F/A Area = pi d^3 / 4 Sum F h = 0, Sum F v = 0, Sum M = 0 The Attempt at a Solution Hey everyone, after reading the question a number of times and not knowing for certain where to start, I figured because the stress and area...

Homework Statement Homework Equations Pitagora's: ##~a^2+b^2=c^2## Maxima/minima are where the first derivative is 0 The Attempt at a Solution $$\left( \frac{a}{2} \right)^2+\left( \frac{b}{2} \right)^2=r^2~\rightarrow~b^2=\frac{16r^2}{a^2}$$ The strength S has the proportion coefficient k...

Hi All, I'm new here and forgive me if I've posted in the wrong section, I'm more of a computer engineering/architect guy asking a physics question. Is it possible to have a projected laser beam repeated across multiple points? between the range of 600nm-900nm ? Example, a pad that takes in...

I have a misunderstanding about the beam splitter in this experiment High fidelity entanglement swapping with fully independent sources Rainer Kaltenbaek, Robert Prevedel, Markus Aspelmeyer,Anton Zeilinger http://arxiv.org/pdf/0809.3991.pdf Part of the diagram is reproduced here Two photons...

This is what I understand about light. Light is electromagnetic wave, it comes from the source, bounces from the objects and we see reflected light. Let's imagine next situation. We are in a dark room and we got only one light source, a toy laser. When we turn it on, we can clearly see beam...

Boyd - Nonlinear Optics page 5, there says 'Here a laser beam whose electric field strength is represented as $$\widetilde{E}(t) = Ee^{-iwt} + c.c$$But why is it written like this? Is it because the strength is the real part of the complex electric field? Then why doesn't he divide it by 2 after...

Hi, I'm quite stuck on this past paper question and would really appreciate some help on it. Below I have attached the questions and solutions; it asks me to determine where the maximum tensile and compressive strain in the beam using the bending moment diagram (attached as separate figure...

Homework Statement How to differentiate between rectangular beam and flange beam ? In the question below , the answer provided is flange beam , I'm wondering can i design it as rectangular beam Homework EquationsThe Attempt at a Solution Since there's no clue whether the flange beam or...

For a 4x4 beam 12' long supported by 4x4 8' tall colums I need to calculate the moment around A and B and the vertical forces at A and B based off the point load which for discussion purposes is in the middle of the beam but could be anywhere on the beam. Does anyone know the calculations? I...

Homework Statement The Figure shows a welded steel bracket loaded by a force F = 5 kN. Homework Equations [/B]The Attempt at a Solution I know that the total deflection is the deflection of the beam due to F. And I also need to take into account the angular deflection at the joint...

Homework Statement An angle is given between 2 polarizer's (45 degrees), through them light passes (unpolarized than after passing through the first one it polarizes), some of the light its shown on the display. For how much does the angle needs to be increased for the intensity of light to be...

Homework Statement A rectangular Cross-section beam, 20cm deep by 10cm wide, is subjected to a maximum bending moment of 360kNm A) Calculate the second moment of area of the beam cross-section B) what is the maximum stress in the beam under this load C) if the value of E for the beam of...

Homework Statement A beam of rectangular cross section 200 mm deep and 100 mm wide. If the beam is 3m long, simply supported at either end. And carries point loads R1 to far left, R2 to far right, 1m to left 5kN load, 2m to left 10kN load. (a) Calculate the maximum bending moment (b) Calculate...

Just has my first CT scan ever for low dose cardiac scoring. Held my breath twice with gantry in fixed position and then once again with gantry spinning. I thought I would have heard the high pitched x-ray when beam energized but didn't at all. All I heard was normal fans and the mechanicals of...

I'm trying to understand differences between two setups. In one setup I put a thin metal layer on top of a rigid plastic film, which I then bend to a certain radius. The metal is not very prone to crack in itself but with very small bending radius you are able to crack the surface. If I have...

Homework Statement I want to design the beam as circled . I am wondering should I design it as a simply supported rectangular beam or simply supported flange beam Someone told me that i should design it as simply supported flange beam . i doubt that it's correct . Homework EquationsThe...

So basically i was solving this question about moments amd while solving it i noticed that beam will always remain balanced as FA will decrease and FB will increase as the man moves forwards thus plank alwats remains in equilibrium but now the question is can it support any weight without...

I would like to know the results of a few scenarios with a beam splitter. (1) You send a single photon through a half silvered mirror with a reflector at either side, as above, but instead of having two detectors, and a 50% chance of either going off, you just have one detector, and where...

I need to settle an argument between two mech eng colleagues... Here goes. There is an infinitely rigid beam running between two walls. The attachment points are fixed. There is a force acting downwards on the center of the beam. The disagreement is on whether there is a reactive torque in the...

I've got a problem where a weight is being held to the side of a building using a beam and a cable. The weight is 336 pounds and the angle between the cable and the beam is 49 degrees. I need to calculate the tension of the cable and the force of the beam. I calculated the force of gravity as...

Is it possible to set mirrors up in such a way that if you hit any area of any of the mirrors, the laser would be brought to a central location in the middle of the mirrors? I'm thinking of a way to transmit data in space via laser where you would want a large target for the laser to hit when...

Homework Statement A beam of molecular oxygen containing 1010 molecules/cm3 and average speed of 500 m/s strikes (elastic collision) a plate at an angle of 30º with the normal direction. Calculate the exerted pressure on the plate. Homework Equations P = Impluse x Flux The Attempt at a...

Hi I am trying to derive an expression for the deflection in a cantilever beam using castigliano's theorem. I have found and attached an example of the solution. I understand the most of what is going on in the attached solution but I don't understand where the b^3 came from in the last line.

Hello, I was wondering if it would be possible to eject chemical compounds from a sample, say like a biological tissue, using an electron beam. I know that electron scattering is one product of electron-specimen interaction, and that's the principle behind electron microscopy, but I'm more...

Homework Statement Many experiments in physics call for a beam of charged particles. The stability and “optics” of charged-particle beams are influenced by the electric and magnetic forces that the individual charged particles in the beam exert on one another. Consider a beam of positively...

I have a question regarding finding the Young’s modulus of a rod by loading a weight to the end and measuring the change in displacement. The experiment is part of my advanced higher physics project on Young’s modulus however it is the only experiment that I’m doing that the book “Tyler” does...

How long is a beam of light or sunlight?

Homework Statement [/B] Consider an electron beam traveling with velocity v. The total current of the beam is I.The beam is of uniform charge density and has radius R. (a) Find E and B at r<R and r>R using Gauss' and Ampere's laws. ( This part is fine.) (b) Consider an electron in the beam at...

Homework Statement Homework Equations in photos The Attempt at a Solution [/B] First approach: Second approach: The two approaches used net force and net moment respectively in order to find reaction force of O, yet they got different answers. Why? Thank you very much!

Homework Statement A Van de Graaff generator is one of the original particle accelerators and can be used to accelerate charged particles like protons or electrons. You may have seen it used to make human hair stand on end or produce large sparks. One application of the Van de Graaff generator...