A hollow steel $E=30,000$ksi tube $(1)$ with an outside diameter of $2\mathrm{.}750$ in $.$ and a wall thickness of $0\mathrm{.}250$ in$.$ is fastened to a solid

aluminum $[E=10,000$ksi$]rod(2)$ that has a $2\mathrm{.}000-$in$.-$diameter and a solid $1\mathrm{.}375-$in$.-$diameter aluminum rod $(3).$ The bar is loaded as

shown. Assume $L_1=65in.,L_2=45in.,L_3=27in.,R=36$kips,$Q=16$kips, and $P=27$kips. Determine

$($a$)$ the change in length of steel tube $(1).$

$($b$)$ the deflection of joint $D$ with respect to the fixed support at $A.$

$($c$)$ the maximum normal stress in the entire axial assembly.

Answers:

$($a$){}_1=$

in$.$

$($b$)u_D=$

i

in$.$

$($c$),{}_{\text{m}\text{a}\text{x}}=$

ksi