Question

Why siphon works only higher to lower elevation only?

Answer 1

The simplest definition of the Siphon Effect is, atmospheric pressure pushes the liquid up and gravity pulls the liquid down. The siphon effect when pertaining to removing ponding water from a flat roof is quite simple. Water always flows from an area under higher pressure to an area of lower pressure. As always, water seeks its level and the higher container empties into the lower container.

Answer 2

Answer:

As always, water seeks its level and the higher container empties into the lower container. You can't use a siphon to lift water higher than 30 feet because above that height, an empty region will develop at the top of the pipe and stop the siphon process.