Liquid Helium II the superfluid (part 1 Introduction and equipment)

A 1963 film by Alfred Leitner demonstrating the remarkable properties of liquid helium when cooled below the lambda point (the superfluid state).

For those interested in 3He more information can be found here:
The Extraordinary Phases of Liquid 3He
http://nobelprize.org/nobel_prizes/physics/laureates/1996/lee-lecture.pdf

Superfluidity in 3He: Discovery and Understandning
http://nobelprize.org/nobel_prizes/physics/laureates/1996/osheroff-lecture.pdf

The Pomeranchuk Effect
http://nobelprize.org/nobel_prizes/physics/laureates/1996/richardson-lecture.pdf

Category:

Science & Technology

Tags:

• Superfluid
• helium
• entropy
• viscosity
• Leitner
• Physics
• statistical
• mechanics

[65farthead]

Exactly what is kalvin?

[Zantorc]

@65farthead The kelvin is a unit for temperature given the symbol K, it's related to the centigrade scale. The temperature of a body is a measure of its thermal motion (the random vibrational motion of the atoms and molecdules making up the body). No thermal motion motion (ignoring quantun mechanics) is 0 K called 'absolute zero' - you cant go lower, which corresponds to -273.15 °C or (-459.67 °F). Water freezes at 273.15 K = 0 °C = 32 °F. Water boils at 373.15 K = 100 °C = 212 °F.

[mreueujj1]

so... the bose einstein state of matter doesn`t apply to helium?

[Zantorc]

@mreueujj1 What gave you that impression?

[jesperlett]

Temperature in Kelvin is not referred to as a degree (°) like Celsius and Fahrenheit e.g. 20 °C and 68 °F. Simply 293.15 K

[Zantorc]

Good point I hadn't spotted that - I'll update the annotation. BTW that convention was only established in 1967/68 (after this film was made). In fact for a long time after 1968 'degrees Kelvin' was still in common use. Strictly speaking when writing the unit 'kelvin' it is lower case and upper case when abbreviated to 'K'.

[Zantorc]

@mreueujj1 It enters the Bose Einstein state at 2.17 K and it is never solid except under pressure.

[nyer070]

Dr. Alfred Leitner, rest in peace you will be always missed, your videos are instructional and great. Also many many thanks to Zantorc for sharing these great videos, god bless you my friend

[InitialDAmine]

@jesperlett Kelvin tempreture= 273+degree tempreture....