Final answer:
The term 'bending gain' is not a standard term in physics, and calculating the bending or deflection of a tube requires knowledge of the material's properties and the applied forces, which are not provided in the question.
Step-by-step explanation:
The question appears to be asking about a concept in physics known as bending or deflection of a material under a load, which may relate to topics such as elasticity and structural engineering. However, the question itself seems to lack sufficient detail to provide a specific answer. In physics, the bending 'gain' is not a standard term, and to calculate bending or deflection of a pipe or tube, one would typically need to know the properties of the material, such as Young's modulus, the moment of inertia, and the type of load applied. Since the information given does not provide these details, it is impossible to offer a direct answer to the question as phrased, and such calculations typically fall outside the scope of what's covered in high school physics.
For a comprehensive analysis, an understanding of the mechanical properties of the tube and forces involved would be required. Additionally, engineering formulas such as the Euler-Bernoulli beam equation may be used to calculate deflection in beams, which could be analogous to the bending of a tube if the proper assumptions and modifications are made. Given the information provided in the references, it seems they relate to different physics problems regarding tension, compression, and resonant frequencies, none of which directly answer the original query about the bending gain of a 1/2" tube bent at 90 degrees.