Let's generalise the problem and assume that the wheel is a massive disk of uniform density and with total mass M. a) Choose a suitable generalised coordinate and write down the corresponding Lagrangian that describes this system. b) Derive the equation of motion. c) What happens if the wheel is really heavy? Take the limit M m1 + m2 and comment on your result. Hint: the rotational kinetic energy of a massive disk rotating about its axis of symmetry with angular velocity is Erot = 1 2I2, with the moment of inertia given by I = 1 2MR2