Two kilograms of air within a piston-cylinder assembly execute a Carnot power cycle within maximum and minimum temperature of 750 K and 300 K, respectively. The heat transfer to the air during the isothermal expansion is 60 kJ. At the end of the isothermal expansion the volume is 0.4 m3 . Assuming the ideal gas model for the air, determine (a) the thermal efficiency. (b) the pressure (in kPa) and volume (in m3 ) at the beginning of the isothermal expansion. (c) the work and heat transfer for each of the four processes (in kJ). (d) Sketch the cycle on p-V coordinates

answer;

d. are made mostly of liquid

explanation;

-the general   composition and structure planets includes; they have a thick gas and liquid layer covering a small,solid core. mostly the gases are hydrogen and helium atmosphere and layers of liquid hydrogen. for instance neptune and uranus are examples of the outer planets, they have a core covered by ice and ammonia.

-neptune's atmosphere is hydrogen and helium with a bit of methane so there is no oxygen to breath and the interior is made up of frozen water and ammonia with a rock and iron core. thus, there is no liquid water or solid surface to survive.

igneous rocks also form where plates converge. the subducting plate melts as it sinks into the crust of the earth, and the melt rises into the overriding plate forming volcanoes. metamorphic rocks are formed mainly in the lithosphere, wherever there is high pressure and high temperature. -woods

80cm/s.

24cm/s.

53.3cm/s.