Answer :
Final answer:
The most suitable beam shape for a factor of safety of 2, if the beam is a solid I-shape, is a wide flange beam because it provides superior bending resistance due to its geometry and wider flanges. Thus, the correct option is a. Wide flange.
Explanation:
When selecting a beam shape with a factor of safety of 2 for a solid I-shape beam in engineering, the options provided are wide flange, H-beam, square bar, and rectangular tube. Among these, the wide flange shape, commonly referred to as an I-beam or W-beam, is designed to offer superior bending resistance due to its wider flanges compared to an H-beam. This makes it an appropriate choice for applications where bending strains need to be minimized and a higher factor of safety is required.
Moreover, the term 'wide flange' itself comes from the wide flanges of the beam which provide a greater surface area to distribute loads. Since the beam's cross-sectional geometry significantly affects its bending rigidity, as described in the reference where the bending rigidity grows with the linear scale of the cross-section, a wide flange beam, thanks to its design and geometry, will meet the requirement of a factor of safety of 2 efficiently.
