Abox of weight 135 n is attached to the end of a dangling spring, stretching the spring by 21.0 cm. what is the weight of an object that would stretch the spring by 69.6 cm?

626 n

244 n

41 n

447 n

Gordon is going for a run through the park, but it is cold outside. the low outside temperature could affect his personal safety.

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.

How to know which equation of motion to use where?explain