Cooling rate of water at ambient temperature?

Question

How long does it take for water at 100 degrees F to cool to 90 degrees F in ambient temperature (about 80 degrees) and at sea level?

Just an average degrees per minute will be great! Thanks

Answer 1

Difficult.

You could get a lower limit estimate by calculating the loss of energy by radiation. (Plank's 4th power law of the absolute temperature in degC  - assuming a perfect black body radiator).

Then there is conduction (into the bench it is sitting on) - you could calculate that too. But it's difficult - differential equations.

Then here is convection: too hard altogether.

Anyway, how much water is there?