Originally posted by twhitehead
I am still of the opinion that the effect is entirely due to heat of evaporation.
It can't be both?
Thermal conduction is a powerful effect in our perception of temperature.
When we touch an insulator the surface rapidly warms as well as the thermal conduction
rate being lower. [because of]
When we touch a conductor the surface draws our heat away and it 'feels' much cooler because
of that.
When you shake the can you are increasing the thermal conduction abilities of the can either
by bringing the conducting liquids in contact with the surface you are holding, or by increasing
internal circulation and thus heat convection, or both.
This SHOULD make the can 'feel' colder.
The fact that the can is apparently ALSO getting cooler doesn't mean that the above effects are not
happening. It also does not tell us which if either effect is dominant.
To tell which is dominant we would have to get data on what [if any] increase the shaking produces
in thermal conduction rates [theoretically or experimentally] as well as how responsive our sense
of temperature is to changes in thermal conduction rates as well as determining our sense of temperature
against an actual change in temperature with constant thermal conduction rates. [in the desired temperature
range at which we are conducting these experiments].
It also might be a factor in the temperature change if the can in the experiment had not fully equalised with its
surroundings then increased thermal conduction between a cold interior and a warmer can surface could cool
the surface without the internal liquids having dropped in temperature.
This is not an easy experiment to wrap up. [the fun ones never are 🙂 ].
That said I still am of the opinion that our sense of hot and cold is dominated by conduction rates over actual
temperature and that such effects could well still dominate even in the presence of an actual temperature change.
I do however acknowledge that I was not expecting such a noticeable actual temperature change and stand corrected
on that front.