problem $3(30$ points$)$

Use either the virtual work method $($unit load method$)$ OR the Castigliano Method $($choose your preference$)$ to determine the vertical displacement at joint $B$ for the truss shown below. Assume the compression members has cross section area $A_c=2\mathrm{.}5-i{n}^2$ while the tension members has cross section area $A_1=0\mathrm{.}6-i{n}^2$ and $E=10600-$ksi. Dimensions $a=6-$ ft and $h=8-ft.$ ENTER YOUR WORK IN THE TABLE PROVIDED.

$Ac=2\mathrm{.}5sq$ in

$At=0\mathrm{.}6sq$ in

$E=10600$ksi

$\backslash$table$[[\backslash$table$[[$MBR$],[$ID$]],$Length in$,N$

kip $,$n or dN$/$dP$,EA$

kip $,$nNL$/$EA$],[AB,,,,,],[BC,,,,,],[$DE$,,,,,],[$AE$,,,,,],[$BE$,,,,,],[$BD$,,,,,],[$CD$,,,,,]]$

Vertical Displacement $($in inches$)$ at $B=$

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