I was thinking about this and couldn’t come to a logical conclusion. Perhaps the more surface of water in contact with the air would make it evaporate faster?
Say I had a 500 gallon aquarium, and in the same room, I had a 40 gallon aquarium. Does the larger aquarium evaporate at a different rate?
Why or why not?
In: Physics
>Say I had a 500 gallon aquarium, and in the same room, I had a 40 gallon aquarium. Does the larger aquarium evaporate at a different rate?
>Why or why not?
Evaporation happens at the surface and is like paint drying. All things equal whether you paint the roof of a small store white or a Wal-Mart white, the paint dries at the same rate. Doesn’t matter if one roof is 1,000 square feet and one roof is 10,000 square feet. The surface dries uniformly and both roofs will be dry to the touch at the same time if painted with the same paint under the same conditions.
Same thing with your two tanks. The 500-gallon tank will ultimately put more water into the air through evaporation than the 40-gallon tank, but if kept under identical conditions in the same room they will empty at the same rate.
If all other factors are equal like temperature, how air can move away from the above the aquarium then the larger will evaporate at a faster rate.
That is if the small aquarium has the same proportion as the larger. Because it is not the volume but surface area that is relevant. You could build a 40 gallon have a larger surface area the 500 gallons.
I suspect even if the shape was identical the smaller would evaporate a bit faster per unit of surface area. The edge is longer compared to the area so more air circulation.
A cube with 40 gallon l has sided with a length off 53 cm so an area of 2480 cm^2 and edge length of 213 cm.
A cube with 500 gallon has sided with a length off 123 cm so an area of 15300 cm^2 and an edge length of 495 cm.
So 6x larger are then the smaller but only 2.3x longer edge.
If you take two identical tank volumes (same shape) and scale them to any size it will take the same amount of time for them to evaporate. This is assuming they are kept at a uniform pressure and temperature.
The rate if evaporation depends on airflow, temperature, ambient humidity, and surface area of water exposed.
If all else is held the same, the rate of water evaporation scales with the amount of the water’s surface that is exposed to air. This intuitively makes sense as evaporation only takes place at the surface.
It depends on the temperature and the area from which it can evaporate. The radius and rate of evaporation have an exponential relation so as you linearly increase radius you exponentially increase the area, exponentially increasing rate of evaporation
Edit: assuming the tank is a circle, it’s the mathematically easiest way to think of it
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