Read about strength | 17 Discussions | Page 1

  1. person123

    Why are two pieces of wood stronger when bound together?

    The answer learned in class is that the two 2*4s are able to distribute the load over both of them, but I don't think this is an actual answer because that's balanced by the fact that each block is half the area. Does anyone know of the reason for this observation? Thanks!
  2. person123

    I Maximum Strain For Samples of Different Cross-Sectional Areas

    I would assume that because the samples are made of the same material they would fail at the same stress and so the same strain. However, the data shows that the sample with a greater cross-sectional area fails at a greater strain, and the two are roughly proportional. Does anyone know what...
  3. TheBlackAdder

    Appropriate tightness of bolts between skateboard and trucks

    As you can see in the pictures below the trucks are attached to the skateboard with four screws nuts and bolts, with a 2~3mm piece of rubber between the truck and the board. I've always wondered if tightening the screws bolts harder, decreases or increases the strength of the 7-layered plywood...
  4. J

    Rod strength help please

    Homework Statement An example in my problem set (homework help) An oak rod is hung from a rigid support. The rod has a diameter = 12 mm, length = 9 m, and a catch plate at its base. a) The maximum mass of a weight that each rod can support. b) The minimum mass of a weight that will break the...
  5. A

    What composition of steel pipe should I use

    Hello, I work in a apparel manufacturing warehouse and i'm planning to upgrade the Jacket Hanger Racks to a rotatable conveyor. So I want to insert new Steel Pipes for hanging the Jackets which will rotate. So, the length of the pipe is 370 cms / 12' 2", and the weight it will be holding is...
  6. E

    Tension test specifications

    Hi, I'm performing tension tests using a dog-bone specimen conforming to ASTM E8 on 6061-T6 extruded aluminum alloy. ASTM E8 says the surface preparation should be as the product specified. The material I ordered is low grade bar stock 2" wide by 0.25" thick. If I am going to reduce the...
  7. Alanay

    Could Walking Like a Gorilla Increase Strength?

    I was just thinking while watching the Zookeeper movie. If a child is born and we teach it how to move on it's legs and knuckles instead of just it's legs would it end up being a great deal stronger than people it's age? I think the most weight ever lifted by man was 450 KG, and an average...
  8. G

    I Fracture and material strength

    Let's assume I have a large block of crystalline diamond, with reported compressive strength of 110 GPa. If the cross-sectional area of the block is 1 m2, then obviously if I apply a force of 110x10^9 N the material will begin to fracture. But what if the pressure of 110 GPa is applied locally...
  9. N

    Thickness of components for equal strength

    Homework Statement Givens: - Each of the 2 cylindrical posts are 0.5 inches thick. - The posts and chain links are made of galvanized steel of identical material composition. - The posts and chain links are solid. - Each post is permanently fixed to unbreakable surfaces. The surfaces will move...
  10. kostoglotov

    How conductors/resistors affect electric fields?

    Disclaimer: I'm not sure if this is the correct forum. An ideal conductor (ideal = no resistance) is essentially taking the electric field at one terminal and connecting it to the other terminal. Charge moves when it is in an electric field, electric field strength is in Volts per meter, or...
  11. I

    Can gene structure determine its "strength"?

    Are certain DNA (genetic) strands structurally better build for survival than others? If yes, is there a term for this? For example, is there a specific order of nucleotides that is harder to destroy than another? Or if there is a specific order/combination of nucleotides that would have...
  12. T

    Can I elevate a bed by 4 inches with PVC and sleep on it?

    Hi everyone, it's my first post! I need to elevate a bed by 4 inches for a while. I did some work on this problem already. Here's all the information I used to reach my conclusion: expected total weight with mattress and occupants = 220.92200 kilograms bed weight = 54 kg = 54,000 grams =...
  13. B

    Formula of Average Magnetic B Field Strength of Large Conductor

    Any one knows how to calculate the magnetic B field strength at a distance from a Large Conductor ? Do we go by average ? thanks
  14. E

    Difference in strength between extrusions and sheet metal

    Hello, How do I take in to account the difference in stiffness when fabricating a part (for example, an L-bracket) from sheet metal or using an extrusion? In particular, where I work, it is "common knowledge" that extrusions are stiffer. How do i factor this in the stress and strain...
  15. C

    Solid solution hardening, concentration dependence

    When you add impurity atoms to a material, the yield strength often increases by a process known as solid solution hardening. This is because the impurity atoms create a barrier to dislocation motion. The literature describing this phenomenon dates back to the 1960s with some famous papers by...
  16. G

    Calculating strength of steel square tubing

    Hello, I'm enrolled in College in the civil engineering program and am looking for guidance with calculating strength of steel square tubing. We are making a project that has parameters. 1- Must be made of steel 2- 4"x6"x36" is maximum OD of section. 3- 14 lbs is maximum weight 4- the load...
  17. B

    How to show the inverse square law from a data set

    Homework Statement Hi there! I have a data set of r (independent variable) and E (electric field strength) (dependent variable). The question asks for a non graphical method to show if there is an inverse square law relationship between the two data sets. -- My attempt: I picked the equation...