I WILL MARK BRAINLIEST! A 2.0 kg bullet is fired into a sandbag sitting on a wagon. The combined mass of the wagon and the sandbag is 4.5 kg. a) If the wagon/sandbag/bullet moved together with a speed of 0.22 m/s immediately after impact with the bullet, with what speed did the bullet enter the sandbag? b) Is this an elastic or inelastic collision? Explain.

Consider a double atwood machine constructed as follows: a mass 4m is suspended from a string that passes over a massless pulley on frictionless bearings. the other end of this string supports a second similar pulley, over which passes a second string supporting a mass of 3m at one end and m at the other. using two suitable generalized coordinates, set up the lagrangian and use the lagrange equations to find the acceleration of the mass 4m when the system is released. explain why the top pulley rotates even though it carries equal weights on each side.