How much does a cloud weigh?

Question

A fluffy fair-weather cumulus cloud is about 1 km across and 1 km tall. Such clouds contain roughly half a gram of liquid water per cubic metre of air. 1. Estimate the mass of water in the cloud. 2. Given that, why does it not fall out of the sky?

Accepted Answer

About 500 tonnes of water, which is the mass of a hundred elephants. It floats because that water is spread as tiny droplets through a billion cubic metres of air that weighs a million tonnes. The mass. Treat the cloud as a cube of side 1 km: volume 10 to the 9 cubic metres. At 0.5 grams of water per cubic metre, the cloud holds 5 × 10 to the 8 grams = 500,000 kg = 500 tonnes. Larger storm clouds, tens of kilometres across with more water per cubic metre, hold millions of tonnes. Why it floats. The water is not a lump; it is about 10 to the 15 droplets each a few micrometres across. Such smal…

How much does a cloud weigh?

Your answer

Discussion

Learn the concepts

Related questions