Under steady state, a compressor is used to increase the pressure of an ideal gas air from 100 kpa to 1 mpa. meanwhile the temperature is also raised from 300 k to 500 k. to be safe, a separate stream of water is used to cool the air down to 320 k while the pressure of air remains unchanged during the cooling process. the temperature of the cooling water increases from 15°c to 30°c, while the pressure of the cooling water remains the same at 1 bar approximately. assume the kinetic and potential energy change is negligible, there is no stray heat transfer from the heat exchanger to the surroundings. draw a p-v diagram, one for air identify state 1 to 3 on air p-v diagram. show work for how to obtain relative pressures and temperatures for this p-v diagram.

Some material consisting of a collection of microscopic objects is kept at a high temperature. a photon detector capable of detecting photon energies from infrared through ultraviolet observes photons emitted with energies of 0.3 ev, 0.5 ev, 0.8 ev, 2.0ev, 2.5ev, and 2.8ev. these are the only photon energies observed. (a) draw and label a possible energy-level diagram for one of the microscopic objects, which has four bound states. on the diagram, indicate the transitions corresponding to the emitted photons. explain briefly. (b) would a spring–mass model be a good model for these microscopic objects? why or why not? (c) the material is now cooled down to a very low temperature, and the photon detector stops detecting photon emissions. next, a beam of light with a continuous range of energies from infrared through ultraviolet shines on the material, and the photon detector observes the beam of light after it passes through the material. what photon energies in this beam of light are observed to be significantly reduced in intensity (“dark absorption lines”)? explain briefly.

Determine the fraction of the magnitude of kinetic energy lost by a neutron (m1 = 1.01 u) when it collides head-on and elastically with a target particle at rest which is 21h (heavy hydrogen, m = 2.01 u).

What kind of simple machine is a catapult?