- 3 Consider Light Trapped Into A Cavity With Reflective Walls It Will Be Continuously Bouncing On Walls In The Same W 1 (73.71 KiB) Viewed 58 times
3.- Consider light trapped into a cavity with reflective walls. It will be continuously bouncing on walls, in the same w
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3.- Consider light trapped into a cavity with reflective walls. It will be continuously bouncing on walls, in the same w
3.- Consider light trapped into a cavity with reflective walls. It will be continuously bouncing on walls, in the same way a gas does, and will exert a pressure on them. This is usually referred to a "photon gas", and its thermodynamic variables are also P, V, T. It can be proved that the press exerted on the walls is given by P = = 3074 where o = 7.5 x 10-12 Pa/K is a constant. And the internal energy is calculated as U = OVT4 Consider a photon gas expanding isothermally from a volume of 0.5 m³ to 2.5 m³ at T = 300 K 1 a) Make a plot of the PV diagram for the photon gas (notice it won't look like an ideal gas). b) Based on your PV diagram, calculate the work done during this process. c) Calculate the change in internal energy. d) Calculate the heat for this process. Is it absorbed or released?