A rectangular polypropylene $E=6,200$MPa bar $(1)$ is connected to a rectangular nylon $E=1,400$MPa bar $(2)$ at flange $B.$ The

assembly $($shown in the figure$)$ is connected to rigid supports at A and $C.$ Bar $(1)$ has a cross$-$sectional area of $A_1=1100m{m}^2$ and a

length of $L_1=1250mm.$ Bar $(2)$ has a cross$-$sectional area of $A_2=2950m{m}^2$ and a length of $L_2=670mm.$ After two loads of

$P=3\mathrm{.}5kN$ are applied to flange $B,$ determine:

$($a$)$ the forces in bars $(1)$ and $(2).$

$($b$)$ the deflection of flange $B.$

$($a$)F_1=$

kN

$F_2=\frac{kN}{?}$

$($b$)u_B=$

$mm$