Lagrange Mechanics Practice Problem

A roller coaster of mass m moves along a frictionless track that lies in the xy plane (x horizontal and y vertically up). The height of the track above the ground is given by y = h(x). (a) Using x as your generalized coordinate, write down the Lagrangian, the generalized momentum p, and the Hamiltonian H-p\dot{x}-\mathcal(L) (as a function of x and p). (b) Find Hamilton’s equations and show that they agree with what you would get from the Newtonian approach. [Hint: You know from Section 4.7 that Newton’s second law takes the form F_\text{tang} = m\ddot{s}, where s is the distance measured along the track. Rewrite this as an equation fo \ddot{x} and show that you get the same result from Hamilton’s equations.]


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