A mass m slides down a frictionless cylinder (as shown below). (a) Write down the Lagrangian for the mass m in cylindrical coordinates located with the origin at the center of the cylinder and with the angle ? measured from the initial position of the mass as shown.(b) Use the Lagrangian method to deduce the normal force on m as a function of ?. (Note: no credit will be given if you do not use the Lagrangian method for this)

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