Beams Definition and 259 Threads

This might look a bit stupid but I have just started beams and I can't understand a part in this example it is to do with finding a general equation of the height at any given point on a tapered cantilever beam can someone please explain

If I combine 2 laser beams of different wavelengths, would I get a beat frequency of the difference between the 2 lasers? Thanks, Bill

I've got a situation where I'll be placing a load (a vacuum pump) on two separate beams. Basically, the pump attaches to a machine with a bolted flange. I'm wondering what would happen if we removed all the bolts except for the top and bottom one and let the pump hang...what the bending...

Suppose you have two coherent microwave beams, one beam at 45 degrees to a reflecting wall and the other one at 90 degrees, with the two beams pointing to the same point on the wall. If the two beams are 180 degrees out of phase and destructively interfere at the point on the wall, will the...

Hi everyone, Recently I faced a problem in calculating bending stress in a long UPN profile "flange" due to concentrated force. It seems that the regular/familiar formula for bending stress in a finite/short element does not applicable in local bending of long/infinite beam. See sketch...

There is a classic result by Tolman, Ehrenfest, and Podolsky that in classical GR, the interaction between pencil beams of light is zero in the case where the beams are parallel, nonzero otherwise. (The case where they're not parallel can always be reduced to a case where they're antiparallel by...

Need to build a bridge 20 foot wide gully. The bridge is 4 ft wide and will be constructed of four by eight ft plywood sheet which is placed on top of 2 composite beams that are 4 ft apart (see link for picture).The 2 composite beams need to take all the load which is 500 lb/ft distributed over...

Homework Statement http://tinypic.com/r/2wbxm2s/7 This is a series of beams pinned together at A, B, C Find reactions at a b c Homework Equations Sum of moments at B has to = 0, sum of Fx = 0, sum of Fy = 0 The Attempt at a Solution Sum of moments about A, anti clockwise +ve...

Recently I have placed here the new - viable by my opinion Concept how to produce fusion. By some reasons I have decided not to file the patent application and so for discussing now I am placing here the description of Cyclic Reactor on base of that Concept. Ioseb (Joseph) Chikvashvili

Homework Statement Calculate the reaction forces at B and D See attached jpeg. The Attempt at a Solution sum of vertical forces By + Dy = 7 + (9*5) Do I then solve for the moment about D or A or B? for moment about D i have: -Dy -7 -(9*5)+9By+(12*2)=0 is this correct, please explain to...

Hi there Just a quick question; when I'm calculating moments in a cantilever beam (in my case a quarter circular one), is there any reason (apart from my own ineptitude) why I shouldn't be able to make the cut and FBD starting from the fixed end? I get different answers when I make the cut...

Hello friends, so i have this problem: A beam under test has a measured radius of curvature of 300 m. The bending moment applied to it is 8 Nm. The second moment of area is 8000 mm4. Calculate the modulus of elasticity for the material. ok so using the engineers bending equation i have...

I posted this as a part of a thread on the classical physics forums, but the doubt wasn't resolved, so I thought this might be a more appropriate place... A fixed beam is considered equivalent to a Simply supported beam (SSB) with a point load at its mid point(and thus having reactions Ra*...

Can someone explain what are the implications for the 13 neutron beams that have been observed at Fukushima? How are they created? What will cause more to be created?

Homework Statement 3. A laser scientist tells you that her He-Ne laser can be focused to a spot size of 5.00 microns. When pressed for details, she tells you that she got this number by measuring the Full Width Half Maximum (FWHM) of the intensity profile of the laser waist. a) What is...

I wish to dampen a boom arm, which at its fixed point is connected to a vehicle (arm length is 5m long). The boom is 'L shaped' is attached to the to of the vehicle and extends 5m in the horizontal, then the second leg hangs down 5m, almost to the ground. The end of the boom arms contains lead...

Hi! I didn't understand how the brewster angle works. Why do I have a polarised beam? Do I need electromagnetism to understand this?

Would General Relativity predict that two initially parallel light beams will converge due to their energy curving space-time? John

Can electricity be transmitted using Concentrated beams without using wires with no energy lost in the process?

Hello people, i have got a few thoughts which i would like to share. I few month ago i foundout that there are laser beams in the frequency range of of microwaves (maser beams). (http://en.wikipedia.org/wiki/Maser) I consider the following situation: If a conducting medium (lets think...

hi i would like to ask a question concerning the application of microwave beams. First: a microwave beam can be thought of as a laser beam but the light it emitts is in the frequency range of microwaves (see Maser)... I was wondering why such beams are not used for medical imaging...

Hi everyone, I am studying the feasibility of using the collision of two beams to obtain nuclear fusion energy. I would like you to recommend me some serious and intersting articles about this. Is there any experiment that does fusion by beam collitions already? Im open to hear about any...

Homework Statement calculate the position from A where the maximum deflection occurs. Your answer should be accurate to 3dp. You may assume IE= 100Mn Homework Equations I'm going to go with EI d2y/dx2 = m (the 2 are meant to be squared) The Attempt at a Solution Is this equation...

Hi. I can't understand one thing in mechanics. I am trying to learn how to solve beams in mchanics. I have a triangular load (a load which changes constantly). Why is the point of application of the net force in the one third of the triangle's base? While dividing a right triangle into...

As of this point. I understand the following. 1. there is almost 90% loss when applied to a laser system. 100 watts in 10 watt beam out. 2. when a beam is split there is also a loss, (amount unknown) 3. if you take a 20 watt beam and (with not loss) split it in two and cross the beams...

Hi all, I have a problem with cantalever beams, the beam is 1m long by 0.1m by 0.1m. A 10Kn force placed at the end of the beam deflecting it down. My lecturer simmulated the problem in Ansys and we all got to do it with him using more dense nodes and solutions to find a more refined answer...

I have attached the original question and my attempt at the solution. I think I am on the right path but I am not sure. Can some one please direct me on if I am right so far and what to do if i am/ am not. Thanks

Greetings, Is there a way to combine multiple lasers beams to create a more powerful beam? If so, what optics are needed? How do they need to be arranged? Thanks

1. Hi all, I'm doing a simulation on 3 different cantilever beam as shown in the attached figure. a) is the beam with only width varying from the base to the free end (height stay constant along the beam) , b) is the beam height varying from the base to the free end (width stay constant along...

Does anyone know the spring constant for a clamped/fixed beam with length L that is uniformly loaded? I know the spring constant for a clamped beam that is centrally load by a point load is k= 192EI/L^3 I know for a uniformly distributed is different.

Hallo I have been thinking about when beam starts to behave like string. My questions are: How much tension do you need to put on a beam before it starts to behave like a string? And when does the behaviour become purely string like? Thanks

how fast are the particles in the 2 beams of a Pulsar traveling? and what happens when two of those beams intersect? do those particles collide at extremely high velocities like in particle accelerators?

It has been a few years since I have done beam analysis, and I really don’t remember how to solve this type of problem so I have been reading up on it. I have found similar situations but nothing that matches the problem I am having. I have a continuous beam of 3 spans with a uniform...

With two electrons emitted from a decaying atom in opposite directions, the speed can easily be greater than the speed of light between the two electrons (e.g. 0.7c in each direction). If two receivers then pick up the electrons, hasn't the information traveled between the two receivers at a...

Can someone explain to me how two parallel electron beams can be attracted to each other according to special relativity. Classical physics says each beam will generate a magnetic field so the beams will be attracted to each other. Relativity says the magnetic field only exists for observers...

Hey Guys, first of all I apologise if this question is posted in the wrong forum section and a mod has to move it to its correct location. I am trying to find information on combining the paths of several laser beams. I have found much complex information pertaining to the combination of the...

Homework Statement An electromagnetic wave in a vacuum /w magnetic field of 265 mG. If the wave is spatially confined to a beam with a diameter of .75mm, how much energy is measured by a photodetector with an active area with diameter 5 cm in one second. The Attempt at a Solution...

Two parallel beams of light going opposite ways pass each other. What speed do they pass at? I'm told they pass at the speed of light? How is that possible, I know in relational math you would add the two speeds but for light it is different right? What math does it use?

I don't know how to do the following question, The beam shown is under the action of a uniformily distributed load w of 2 kN/m between the supports and a point load of 2 kN at the end point. Determine the bending moment in kNm at point A situated 3 m to the right of the left support. Round off...

http://www.math.columbia.edu/~woit/wordpress/?p=2819 ==quote== High Energy Beams at the LHC At 5:23 am in Geneva this morning, for the first time the two LHC beams were ramped up to high energy, the 3.5 TeV/beam that they plan to run at for the next two years. These are the highest energy (per...

Can anyone tell how the intensity of lasers beams is measured. What equipment is used. Any relevant equations?

Hi, In a cantilever beam with a load on the free end, at a point on the neutral axis, will the normal stresses (due to bending stress and axial stress) be zero? Or am i wrong? And if i was to draw a Mohr circle for that point at the neutral axis, would the center of the circle be the origin? I...

When 2 particle beams meet head on, more energy is avaliable than when the particle beam is directed at a fixed target. Why is this? My textbook gives an explanation which I don't understand, involving rest mass energy. Any alternate explanation or explaining the one given will be great...

find the ratio of d/b such that the largest stress in the beam will be minimum i know that the maximum stress is σmax=Ymax\frac{M}{I} and i know that for a rectangle I=bh3/12 now in the question i am asked to find the ration of the (diameter of the log)/(the width of the rectangle) such...

General Questions About "sizing" Structural Beams. Hello Guys. I would like to know where I can find high quality info on which types of beams to use for certain applications. Say, for example, a 100 foot span which is supposed to hold 100 tons at the center, or cantilever, and so on. I know...

Two perfectly coherent laser beams point at two different positions on a screen. The energy transmitted by each of the beams is dissipated at the screen - it's either reflected (and thus visible to an observer) or becomes a potential energy of some sort. Now both beams are pointed at a single...

Last night the LHC re-established circulating beams. CERN has issued a http://press.web.cern.ch/press/PressReleases/Releases2009/PR16.09E.html" .

Homework Statement Hope you can access this link for question http://s353.photobucket.com/albums/r387/james_nikko/?action=view&current=img002.jpg Supports are at 1.5m and 4.5m Homework Equations The Attempt at a Solution Ok so i have attempted the problem using the following (5x1.5) + (5x3)...

Deflection of Beams - Rearrange formula [URGENT] Homework Statement Deflection for a simply supported beam... I calculated the deflection of it to be 9.72mm downwards, but there is a support 6mm from the original position and need to calculate the force on the support... The original...

Dear Particle Physicist, I'm unable to find an equation for the CM energy to use for when colliding beams have different masses and energies, for example the HERA colliding electron beams with proton beams. If you know a website, and can write the equation I'd be grateful. Thanks in advance