# Dropping one at a time

A helium-4 atom falls from a height h into a tank of gaseous helium atoms at 300 K. What is h in meters if the temperature of the helium atoms remains at 300 K after the falling atom enters the tank?

Details and assumptions

• The acceleration of gravity is $$-9.8~m/s^2$$.
• As the atom falls it is in vacuum.
• The atom starts from rest.
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