QUESTIONS of air at standard pressure (76 cm Hg). Compare this value with the va
ID: 3279864 • Letter: Q
Question
QUESTIONS of air at standard pressure (76 cm Hg). Compare this value with the value of 2.7 x 104 iu the "Handbook of Chemistry and Physics," Chemical Rubber Company (CRC). 1) Given that (n -1) of a gas is directly proportional to the pressure, calculate the refractive 2) When it was stated that the refractive index of a gas is directly proportional to the what is it that was inherently assumed about the temperature? Estimate the ratio of the density of glass to the density of air by assuming the crude model that 3) (n -1) is proportional to the density. Compare this ratio to the ratio of densities (abou obtained from the CRC handbook. 4) What is the role of the 18-mm lens in the experiment? 5) Why do you see fringes cross the field of view as you lower the pressure in the cell? 6) Does the variable thickness of the 18-mm lens affect the interference pattern'? 7) Why can we drop consideration of the thickness of the glass used in the air cell in PartII?Explanation / Answer
We know that the refractive index of air is given by
n(P,T) = 1+0.000293*rac{PT_0}{P_0 T}
n-1 = 0.000293*P/P0
This means that from the given assumption it implemented that T = T0 = 300K. Now the refractive index of air at 76mm of Hg pressure is
n = 1+0.000293(P0/P0) = 1.000293