The structure is subjected to the loading shown. Member AD is supported by a cable AB and roller at C and fits through a smooth circular hole at D. Member ED is supported by a roller at D and a pole that fits in a smooth snug circular hole at E. Determine the x, y, z components of reaction at E and the tension in cable AB. z C A D B E 0.3 m y 0.3 m 0.5 m 0.4 m F {2.5k} kN x 0.8 m Prob. 6117

Energy Kinetic Energy - energy of motion Potential Energy - stored energy Linear Kinetic Gravitational Potential Q: What about the spring potential Spring Potential Lagrange's Equations/Method (Sec. 1.5) * Energy-based method * Allows us to ignore internal/interaction forces (if we want to) * Usually based around: - generalized coordinates - virtual displacements Generalized Coordinates Lagrange's Equation (with no external forces or damping) Simple Linear Example of Lagrange's Method Simple Rotational Example of Lagrange's Method A Less-Simple Example (Newton/Euler) A Less-Simple Example (Lagrange) Lagrange's Met