Question $1(25$ marks$).$

Consider the structure shown in Figure Q$1.$ The structure is subject to point $l_0$ at nodes $H$ and $E.$ The point load at node $E$ is perpendicular to the member $E_f$ Furthermore, all the members have the same length. Answer the following questions:

$($a$)$ Find the reaction forces $($direction and magnitude$)$ at nodes J and D$.$ Show, complete free$-$body diagram.

$5$ Ma

$($b$)$ Using the joint resolution method, determine the internal forces in members $AJ,IJ,AI$ and AB $.$ Indicate whether the member is in tension or compression.

$[8$ Mar

$($c$)$ Using the method of sections, determine the internal forces in members GC$,CD,GH,$ and BC $.$ Indicate whether each member is in tension or compression. Show the proper section with its free$-$body diagram.

$[12$ Mark

Figure Q$1.$ This figure shows a truss supported by Node J on the bottom left and Node E on the wall on the top right. There are two external loads, $3$ kN at Node H downwards and $5$ kN at Node E$.$