Which list includes the phase changes that require a loss of energy (heat)? a. sublimation and deposition
b. condensation, freezing and deposition
c. freezing and melting
d. melting, vaporization and sublimation

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.

Glass has a hardness that is in the middle of the hardness scale. what is the hardness of glass?

What component of earth’s atmosphere exists entirely as a result of photosynthesis?