Deflection Calculation using virtual work method. Determine slope at A and vertical deflection at point D of the beam loaded as shown in the figure below using virtual work method. The cross section of the beam is constant throughout its length and moment of inertia is $150$ x $10^6$ mm$^4.$ A is a roller support, and C is a fixed. There is an internal pin $($hinge$)$ at point B$.$ Take E $=200$ Gpa.