• Question: Why does rain come in drops and not in a continuous stream?

    Asked by dong to Mike, Pip, Tianfu, Tim, Tom on 29 Jun 2012.
    • Photo: Tom Lister

      Tom Lister answered on 29 Jun 2012:

      You have clearly never been to Cornwall!!

      Clouds are formed by very small droplets of water which are pulled up from the sea/lakes ground in currents of warm air. When they eventually become so numerous that they keep banging in to each other and joining together, they form big droplets that are too heavy to be held up by the currents and so fall to the ground – rain.

      They would have to be held up by some very strong force to keep joining together long enough to form a constant stream, and even then they might spread out on their way down (like when you fire a hose up in the air and its spread out into droplets before it hits the ground)

    • Photo: Tim Stephens

      Tim Stephens answered on 29 Jun 2012:

      It’s because of surface tension. Water wants to be in the simplest shape that it can be, and that means droplets when there’s not much of it about (like in a raincloud). It’s only when you have lots and lots that you get a continuous stream.

Comments