The Siphon

A Siphon is a bent tube made of rubber tube or glass used for transferring liquid from a vessel.

The arrangement of a siphon is such a way that the short arm is in the vessel of the liquid at higher level while the longer arm is at lower level

liquid flows from the higher vessel to the lower vessel because the pressure tending to force the liquid up to the tube at the higher level is greater than the pressure to force the liquid up at the lower level.

From the diagram above,

Atmospheric  pressure = pressure at A + Pressure due to AB = Pressure at D + Pressure due to BD

Because BD is greater than AB pressure at A is greater than pressure at D

Pressure at A =Pressure  at C

The difference in pressure causes the liquid to flow from A to D  is hρg. Where h is height A to D

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