/sci/ - Science & Math

'sup /sci/

My friend needs help with some work for her engineering degree (I'm doing physics) which involves energy transfers. We've got through most of them, but there are a few where I simply can't seem to translate what's happening into energy transfer. Those are:

1) a nozzle on the end of a hose accelerates water out of it
2) air is compressed in an insulated piston-cylinder arrangement
3) air expands into a volume previously held at vacuum

The format she's meant to answer in is (for the case of water in a dam generating electricity):
Gravitational Potential -> Kinetic -> Mechanical -> Electrical

Any help would be appreciated, although I understand the reluctance of people to threads like these.

whats going on in this thread?

http://hardsci.wordpress.com/2013/09/17/the-hotness-iq-tradeoff-in-academia/

In Tesla's "World-System" of wireless power transmission, is the existence of the Earth's atmosphere a requisite?

Could this form of wireless transmission be accomplished on other bodies, having or lacking an atmosphere?

Could this technology power things far from the Earth?

What do you think the world would be like had Tesla completed the Teleforce?