The stress (in Pa ) in the link AB is ---
Extracted text: In the figure, the load P = 1 N, length L = 1 m, Young's modulus E = 70 GPa, and the cross-section of the links is a square with dimension 10 mm x 10 mm. All joints are pin joints. 45° 45 B L A The stress (in Pa) in the link AB is (Indicate compressive stress by a negative sign and tensile stress by a positive sign.)