Atank with a flat bottom is filled with water to a height of 4 meters. what is the pressure at any point at the bottom of the tank? (you can ignore atmospheric pressure when calculating your answer)

-- Each square meter of the bottom of the tank has 4 cubic meters
of water standing on it.

-- 4 cubic meters of water is equivalent to 4,000 liters.

-- So its mass is roughly 4,000 kilograms, and its weight is roughly
(4,000 x 9.81) = 39,240 newtons.

-- So the pressure on the bottom is roughly 39,240 newtons per
square meter, or 39,240 pascals, or 39.24 kPa. 

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