Define the following parameters: Bar diameter, 2c = ______________ Radius of bar c = _______________ Torsional constant J = c4/2 = ____________________ Conversion from degrees to radians: ________________ Initial gage length of bar L = _____8 inch____________ Plot the following two graphs: Torsional shear stress versus the shear strain Identify on the graph the proportional limits and the shear modulus G. Show how G is determined experimentally. The shear stress is along Y. Torque T versus angular rotation Identify on the graph the proportional limit. The torque is along Y. Required Sample Calculations: All equations are provided on the lab background. Write the equation first then the numerical calculation and last the results including the units. Torsional shear stress MAX Torsional shear strain MAX Modulus of rupture (MOR) Tensile proportional limit Shear modulus of rigidity G