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In 1995 a research group led by Eric Cornell and Carl Wiemann at the University of Colorado successfully cooled Rubidium atoms to the 20-200 nK temperature range. Assuming (incorrectly) that the Rubidium atoms behave like particles of a classical ideal gas, calculate the RMS speed of a Rubidium atom at a temperature of 85.0 nK. In the experiments one particular isotope of Rubidium was used, Rubidium-87. The molar mass of this isotope is 86.91 g/mol.

User Kristal
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Answer:

0.00493 m/s

Step-by-step explanation:

T = Temperature of the isotope = 85 nK

R = Gas constant = 8.341 J/mol K

M = Molar mass of isotope = 86.91 g/mol

Root Mean Square speed is given by


v_r=\sqrt{(3RT)/(M)}\\\Rightarrow v_r=\sqrt{(3* 8.314* 85* 10^(-9))/(86.91* 10^(-3))}\\\Rightarrow v_r=0.00493\ m/s

The Root Mean Square speed is 0.00493 m/s

User Cyanfish
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