For the $$2D$$ truss with the applied loads shown below, the strain energy in the member $$XY$$ is _______________ $$kN$$-$$m$$. For member $$XY$$, assume $$AE = 30$$ $$kN,$$ where $$A$$ is cross-section area and $$E$$ is the modulus of elasticity.

For the truss shown below, the member $$PQ$$ is short by $$3$$ $$mm.$$ The magnitude of vertical displacement of joint $$R$$ (in $$mm$$) is ______________________

A uniform beam ($$EI=$$ constant) $$PQ$$ in the form of a quarter-circle of radius $$R$$ is fixed at end $$P$$ and free at the end $$Q,$$ where a load $$W$$ is applied as shown. The vertical downward displacement, $${\delta _q},$$ at the loaded point $$Q$$ is given by : $${\delta _q} = \beta \left( {{{W{R^3}} \over {EI}}} \right).$$

Find the value of $$\beta $$(correct to $$4-$$decimal places). _____________________

The members $$EJ$$ and $$IJ$$ of a steel truss shown in the figure below are subjected to a temperature rise of $${30^ \circ }C.$$ The coefficient of thermal expansion of steel is $$0.000012$$ per $${^ \circ }C.$$ per unit length. The displacement ($$mm$$) of joint $$E$$ relative to joint $$H$$ along the direction $$HE$$ of truss, is