1. D

    Support reactions for a beam at an incline

    img: Hello I have a problem with calculating the support reactions for a beam. Lefts side of beam has a pin connection so it takes both Fx, Fy. Right side of the beam has a horizontal roller and it takes only Fy in the direction of the wall. Therefore at the pin...
  2. O

    How far will the middle point of the beam sag under load?

    There is a wooden beam with given size. We put 1kg in the middle point of beam. Question is how much will the middle point lower itself? Young modulus is 1,18x10^10 Pa Size of beam: length 1 meter , other two dimensions are 5cm and 0,5cm The beam is supported on the ends of it. We...
  3. L

    Simple Question - Preloading of a Cantilever Beam

    Hello, everyone. I have been trying to understand the meaning of the question from the posted image. I think that preloading has to do with adding bolts to the cantilever beam such that it can withstand the force from above, but I am not sure how exactly these bolts should be implemented...
  4. N

    Bring a laser beam to the center of a telescope, undependent of initial angle

    Sry for the confusing title, I don't know a better one for my Problem ;) Ok, i struggle with the following: I have a laser beam that gets reflected with an AOD (to different angles), then moves through a beam expander and a collimator and hits a telescope, that focuses the beam to a small...
  5. C

    beam energy

    The question is in the image file and the answer is in the PDF file. My problem is that I don't understand the answer to the question (i) Thanks in advance
  6. L

    determine forces in beam with hinges

    Is it possible to find the VA , VB and VC without ' breaking ' the beam into 2 parts ? 2. Relevant equations 3. The attempt at a solution Here's my working , i gt Moment about A = 10(1) -VB(2) -VC(4) +5(3)(4 + (3/2) ) = 0 Hence , 92.5-2VB -4VC= 0 moment about B = VA(2)...
  7. L

    maximum deflection / slope of beam

    For part a ) , my ans is EI(d2y/dx2) = - Px For part b) , my ans is EI(dy/dx) = -P(x^2)/2 +c1 EIy = -P(x^3)/6 +c1x +c2 at x= 0 , y = 0 , so c2 = 0 , at x = 0 , dy/dx = 0 , so c1 = 0 , so , EIy = -P(x^3)/6 , so , EIy max occur at L=3 , so EIy max = -10(3^3) / 6 = -45 , but the ans is EIy...
  8. D

    Beam reducer

    Hi, i am sorry for my english. i would like to ask you how to calculate the angle gamma for beam reducer by following link: There is beam expander. I want to calculate the same example for beam reducer. How the formula...
  9. L

    shear stress at particular point in beam

    In the example , i suspect the selected A (area) is wrong... From the notes , A' is the area of top (or bottom ) portion of the member cross sectional area . But , in the example , we could see that the selected area is located to the right of the point where shear stress is calculated , is the...
  10. L

    shear stress in hollow beam

    I m going to find the shear stress at section n-n . So , shear stress in beam has formula of τ = V(Ay) / It I gt the I ( second moment of inertia correctly ( same as the given ans ) , but I'm having problem of finding the shear stress at A . For V ( shear force ) , it is 40kN...
  11. L

    Wavelength and kinetic energy of crystally diffracted neutron beam.

    A beam of neutrons all with the same energy are diffracted by atoms which are seperated by 0.0910 nm in a crystal plane. At the angle $\theta = 28.6^{\circ}$ the instensitymaxima for $m=1$ is observed. What is the neutron wavelength and the kinetic energy expressed in eV?
  12. N

    Can combining invisible EM waves, together as a single intertwined ray, make the beam

    Can combining invisible EM waves, together as a single intertwined ray, make the beams become EM waves that get absorbed by electrons, and? - change from waves that traverse solid matter. Like if you mixed radio, X-rays, and gamma waves together, would they become waves that get absorbed by...
  13. M

    Simply supported beam

    Hello, I'm a bit confused on my coursework when calculating the bending moment, friends are saying different things and I don't know anymore. We have a thin walled cylinder that is simply supported over 8m and it has a mass of 15000kg. The inner diameter is 1750mm and it has a wall thickness...
  14. J

    Weight/Torque of a beam

    I have a 100cm beam with the fulcrum at the 20cm point. At the 0cm point is 300g which puts the beam into balance. How can I find the total weight of the beam and the torque due to the weight of beam using the given information.
  15. P

    deflection od continuous beam

    Hi, The problem uses a continuous beam, but I'm unsure if I'm correct in solving for the max deflection between pts A and B (I've included the BM and SF diagrams btw pts A snd B, only). Deflection should be a maximum when SF = 0. I've also formulated an equation to solve for max deflection...
  16. S

    beam combiner

    Hello, Does anybody know the matrix representation of a beam combiner? thanks
  17. H

    Concrete Beam Exposed to Fire

    In the example a reinforced concrete beam is subjected to a "standard fire" on three sides. Does anyone have an idea on how to solve this question? I really don't have a clue. I have attached the question below.
  18. D

    This term in beam atmospheric transmittance?

    Not quite sure where this fits, but I'll chance it that it goes here. I've started reading up on the basic science behind solar energy technology, mainly because I find the subject interesting. However, I've come across a term in one of the equations that I'm honestly not sure where it comes...
  19. C

    Reactions of the beam

    Can anyone help me with this problem? Here is my effort. W2 = 1/2 bh = 400(12)/2 =2400lb My question is, how will I solve for the location of the W2? Thanks in advance.. ^_^
  20. M

    loaded beam and reaction

    a uniform horizontal beam ABCDE of weight 4 kn is simply supported at B and D. AB = BC = CD = 1.0m, and DE = 1.5m. loads of 20kN , 30kN and 10kN act at A, C and E respectively, and i uniform distributed load of 5kN/m act between C and E. (a) Draw the loaded beam to scale (b) hence ot otherwise...