Question 191036
In problems 11 and 12, use the fact that the load a beam with a rectangular cross section can support is jointly proportional to the beams width and the square of its depth and inversely proportional to it's length.
load  = k[wd^2/L]
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11. A beam 2 cm wide and 5cm deep can support a load of 630kg. What load can it support when turned on its side? 
1st You need to solve for "k"
630 = k[2*5^2/L]
630 = k[50/L]
k = 630L/50 
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Now you know the equation for this beam is load = [630L/50][wd^2/L]
load = 630wd^2/50
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Now if you turn the beam on its side w = 5 and depth = 2, so you get:
load = 630*5*2^2/50 
load = 630*20/50
load = 630(2/5)
load = 126*2 = 252 kg
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Cheers,
Stan H.





please please please explain what you are doing if you answer this problem. it is so confusing i cant even think of what to do.