Repeat: The MFP of air at atmospheric pressure is very short, 70 nm, but at 100 mPa (~6997100000000000000♠1×10−3 Torr) the MFP of room temperature air is roughly 100 mm, which is on the order of everyday objects such as vacuum tubes.
The MFP of air at atmospheric pressure is very short, 70 nm, but at 100 mPa (~6997100000000000000♠1×10−3 Torr) the MFP of room temperature air is roughly 100 mm, which is on the order of everyday objects such as vacuum tubes.