Determine the average pressure applied to an aquarium that is 25 cm long and 20 cm high if it is completely filled with water.

Data: L (aquarium length) = 25 cm (0.25 m); h (aquarium height) = 20 cm (0.2 m); the taken aquarium is completely filled with water.

Constants: ρ (density of water in the aquarium) = 1000 kg / m3; g (acceleration due to gravity) = 9.81 m / s2 ≈ 10 m / s2.

The average force of pressure on the wall of the taken aquarium can be calculated by the formula: Fst = 0.5 * ρ * g * h * Sst = 0.5 * ρ * g * h * L * h = 0.5 * ρ * g * h ^ 2 * L.

Calculation: Fst = 0.5 * 1000 * 10 * 0.2 ^ 2 * 0.25 = 50 N.

Answer: The average pressure force is 50 N.