Before revision: Looking at any point on the column, we can write the moment equilibrium: where the right-hand side of the equation is the moment of the weight of BP about P. According to Euler–Bernoulli beam theory: Where is the Young's modulus of elasticity of the substance, is the moment of inertia .
After revision: Looking at any point on the column, we can write the moment equilibrium: where the right-hand side of the equation is the moment of the weight of BP about P. According to Euler–Bernoulli beam theory: Where is the Young's modulus of elasticity of the substance, is the second moment of area .