De Marssumermolen, Marssum 57 cogs. This drives the "wallower" (31 cogs) at the top of the "upright shaft". At the bottom of the "upright shaft" there are two "crown wheels"' The upper "crown wheel", which has 17 cogs drives an Archimedes' screw. The axle of the Archimedes' screw is diameter and long. This screw is used to pump water into the polder. The lower "crown wheel", which has 43 cogs, drives a gearwheel with 38 cogs on the axle of an Archimedes' screw, which is used to drain the polder. The axle of the screw is diameter and long. The screw is diameter.
Archimedes' principle immersed in a liquid, the liquid exerts an upward force, which is known as the buoyant force, that is proportional to the weight of the displaced liquid. The sum force acting on the object, then, is equal to the difference between the weight of the object ('down' force) and the weight of displaced liquid ('up' force). Equilibrium, or neutral buoyancy, is achieved when these two weights (and thus forces) are equal. Archimedes' principle does not consider the surface tension (capillarity) acting on the body. Moreover, Archimedes' principle has been found to break down in complex fluids. Archimedes' principle shows the