Instead of the arrangement in Fig. 21.8, the speed of molecules can also be measured with a rotating slotted-disc apparatus, which consists of five coaxial 5.0 cm diameter discs separated by 1.0 cm, the slots in their rims being displaced by 2.0° between neighbours. The relative intensities, I, of the detected beam of Kr atoms for two different temperatures and at a series of rotation rates were as follows:

Find the distributions of molecular velocities, f (vx)' at these temperatures, and check that they conform to the theoretical prediction for a one-dimensional system.

Transcribed Image Text:

v/Hz I (40 K) I (100 K) 20 0.846 0.592 40 80 100 0.513 0.069 0.015 0.485 0.217 0.119 120 0.002 0.057