A. Show that, if the ratio of the blackbody fluxes from a star at two different frequencies (i. e., a "color") is measured, then, in principle, the surface temperature of the star can be derived, even if the star’s solid angle on the sky is unknown (e. g., if it is too distant to be spatially resolved, and its distance and surface area are both unknown).

b. Explain why it will be hard, in practice, to derive the temperature measurement if both frequencies are on the Rayleigh-Jeans side of the blackbody curve, hν >> kT.

c. For the case that both measurements are on the Wien tail of the blackbody curve, hν >> kT, derive a simple, approximate, expression for the temperature as a function of the two frequencies and of the flux ratio at the two frequencies.

d. If, in addition to the flux ratio in (c), a parallax measurement and the total flux (integrated over all frequencies) at Earth are available, show that the star’s radius can be derived.

Drag each item into the proper state of matter category.

Air initially at 0.75 bar, 1000 k, and occupying a volume of 0.12 m^3 undergoes two processes. process 1-2: the air is compressed isothermally until the volume is halved. process 2-3: the air undergoes a constant pressure process until the volume is halved again. assume ideal gas behavior. a) determine the mass of the air, in kg. b) the work and the heat transfer for each of the two processes, in kj. (100 kj = 1 bar . m^3)

When temperature of a substance increases, of its particles increase resulting in more between particles. real world applications of thermal expansion absolute zero (-273 degrees c) is the lowest possible temperature on the kelvin scale. it is a measure of where a substance has no kinetic energy. heat is a process of the . energy flows spontaneously from a object to a until equilibrium is reached. heat is measured in heat is transferred throughis a method of heat transfer that occurs between particles of matter that are in direct contact with each other. are poor conductors that impede / reduce the rate of heat transfer. is a method of heat transfer that occurs in fluids (non-solids) by means of currents. real world application of convectiona method of heat transfer through electromagnetic waves. when energy moves from one object to another inside a closed system, no energy is or in the system in the transaction. systems will spontaneously move to a state of organized energy or high disorder over time called