Recent content by haynewp

  1. H

    Was bored today and searched for a puzzle. Came across this one....

    https://www.mensa.org.uk/puzzles/brainteasers?page=470
  2. H

    Was bored today and searched for a puzzle. Came across this one....

    Hmmm...appears to have turned out that the question actually wasn't trivial at over 40 replies later. This is because of the question's poor wording. It is a trivial question if it is worded correctly. Thanks for the solution that was posted which cleared up the confusion for me. And no it...
  3. H

    Was bored today and searched for a puzzle. Came across this one....

    So I am missing something in this one. The answr is 8. Can someone explain? In a department store, with only one girl working on the gift-wrapping service, four gifts per hour were wrapped in the first 15 hours. With help from a colleague for the next 45 hours, the amount of gifts wrapped rose...
  4. H

    How to Solve Forces in Mechanics Problem B and C in Norway?

    I went ahead and solved it. There is actually one other step I used prior to summing moments about point C. You still have to isolate part of the structure as noted above which is the most important idea for this problem. I also found your vertical reaction at D looks like it is going in the...
  5. H

    How to Solve Forces in Mechanics Problem B and C in Norway?

    the reactions at the supports look correct. you need to isolate the top portion of the structure (sum moments about C) to start getting answers.
  6. H

    Statically indeterminant problem

    I summed moments about A and the resultant of the components shown doesn't go through point A so you can get V2 and therefore V1. I just solved the rest of it with what he gave assuming a RIGID BODY, using superposition and the geometry given. The additional equation is that H1=H2 for each...
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    Statically indeterminant problem

    This probably should be placed in the homework help section. Your original resultant force appears to go through point A (ie. try summing moments about point A to start finding reactions).
  8. H

    Need help determining force behind certain vectors

    Make a FBD of the weight with the 2 cables cut. Sum forces in the horiz and vert directions to get the force in each cable.
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    Static tests of timbers in structural sizes (ASTM D198-84)

    I know wood grows on trees, and I never said you shouldn't estimate it for general purposes from the NDS handbook. Anyone (you?) that has done experimental work would know that you also want to verify the properties EXPERIMENTALLY for the specimen you are working with for your data and not just...
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    Static tests of timbers in structural sizes (ASTM D198-84)

    I still say that you want to measure the modulus of elasticity for the actual piece of wood that you have, and not pull the modulus from NDS tables. This is because you are under experimental circumstances and not design. Alephzero is likely correct about bearing failure at the supports, but...
  11. H

    Trying to make a cantilever with the highest efficiency

    A triangle shaped truss should give the least material for a required strength. But I normally can't use these in practice because of the depth required for them. The most common case you will find is floor beams that are cantilevered out to create a balcony, or roof beams that are...
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    Static tests of timbers in structural sizes (ASTM D198-84)

    I have not done this test but I have done the same bending test setup on concrete beams. I would say when rupture of the bottom wood fibers occur visually, and this should correspond to a maximum on the loading data recorder. You should see from the recorded loading data a maximum load point...
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    Finding the reaction of a beam

    Go through the statics tutorials. http://web.umr.edu/~bestmech/
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    Beam Loading and Superposition Method

    Use virtual work. Set the deflections equal for each case and solve for P. I would guess this is how your instructor wants it to be solved and not just by manipulating existing tables.
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