First Law of Thermodynamics Stone Mountain near Atlanta GA h

First Law of Thermodynamics: Stone Mountain near Atlanta, GA has a skyride which is a gondola suspended from a cable that takes people to the top of Stone Mountain as well as back down. Using the First Law of Thermodynamics, what would be the most efficient way to design this ride? Discuss if this might be used to generate rather than use electrical energy. If so, what would be required? If not, why not?

Solution

first law of thermodynamics states that the net heat given to a system is equal to the net work done by the system, when there is no change in internal energy of the system.

if we take one of the human bodies as a system, we take that to the top, and bring it back, there is no change in energy level, and no thermodynamically relevant heat exchange (ignore the temperature variation with altitude) so the system cannot do any work.

if we take the skyride as a system, it is undergoing a cyclic process, it means no change between initial and final states, in this case, net heat given to the system will be equal to the net work done by the system. There is no way the skyride will work by giving out extra work, it may give the exact amount of work as the energy consumed, which is by first law; possible, but will be considered as a ppm (perpetual motion machine) in second law. means it is practically impossible.