Where is 75% of Earth's volcanoes in the pacific ring of fire A) All the smallest tectonic plates are along the ring of fire
B) there are a lot of subduction zones in the Ring of Fire
C) All of the earth mountains are along the Ring of Fire
D) There is a very large volume of water in the ring of fire

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.