Current Attempt in Progress

Two aluminum plates, each having a width of $b=4\mathrm{.}9in.$ and a thickness of $t=0\mathrm{.}750in.,$ are welded together as shown in the figure. Assume $a=2\mathrm{.}5in.$ Specifications require that the normal and shear stress magnitudes acting in the weld material may not exceed $32$ ksi and $20$ ksi, respectively. Determine the largest axial load $P$ that can be applied to the aluminum plates.

$P_{\text{m}\text{a}\text{x}}=$

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