Q$3.$

$($a$)$ The truss framework in Figure Q$3$a is loaded by $20$ kN at point $\text{'}$c$\text{'}.$ Use the Unit Load Method to calculate the vertical deflection at point $\text{'}$b$\text{'}.$ Assume EA $=1\backslash$times $10.$

$($b$)$ The truss is now supported by an additional simple support at point $\text{'}$b$\text{'},$ as shown in Figure Q$3$b$.$ Calculate the vertical reaction force at the newly added support $\text{'}$b$\text{'}.$

Figure Q$3$b$.$