Question

бетонна плита розмірами 2 на 4 на 0,5 метра занурена у воду. Визначте виштовхувальну силу і вагу плити у воді.​​

Answer 1

Відповідь:

39200 H, 54880 Н

Пояснення:

1)Об'єм бетонної плити становить 2 х 4 х 0,5 = 4 кубічних метри.  Густина води становить 1000 кг/м³

а) Вага витісненої води становить 4 х 1000 х 9,8 = 39200 Н. Отже, виштовхувальна сила, що діє на бетонну плиту, дорівнює 39200 Н.

2) Густина бетону становить близько 2400 кг/м³

а) Вага бетонної плити в повітрі становить 4 х 2400 х 9,8 = 94080 Н.

б) Вага бетонної плити у воді становить 94080 - 39200 = 54880 Н.

Answer 2

The Buoyant Force and Weight of a Concrete Slab in Water

When a solid object is submerged in a fluid, it experiences two opposing forces: the buoyant force and its weight. The buoyant force is the upward force exerted by the fluid on the object, while the weight is the downward force due to gravity. To determine the buoyant force and weight of a concrete slab submerged in water, we need to consider the properties of the slab and the fluid it is submerged in.

Properties of the Concrete Slab

The concrete slab in question has dimensions of 2 meters by 4 meters by 0.5 meters. To calculate the volume of the slab, we multiply its length, width, and height:

Volume of the slab = length × width × height Volume of the slab = 2 m × 4 m × 0.5 m Volume of the slab = 4 m³

The weight of the concrete slab can be calculated using its density and the acceleration due to gravity. The density of concrete typically ranges from 2200 kg/m³ to 2500 kg/m³. For this calculation, let's assume a density of 2400 kg/m³:

Weight of the slab = density × volume × acceleration due to gravity Weight of the slab = 2400 kg/m³ × 4 m³ × 9.8 m/s² Weight of the slab = 94,080 N

Properties of Water

The fluid in which the concrete slab is submerged is water. The density of water is approximately 1000 kg/m³, and the acceleration due to gravity is 9.8 m/s².

Buoyant Force

The buoyant force exerted on an object submerged in a fluid is equal to the weight of the fluid displaced by the object. In this case, the buoyant force is equal to the weight of the water displaced by the concrete slab.

To calculate the buoyant force, we need to determine the volume of water displaced by the slab. Since the slab is fully submerged, the volume of water displaced is equal to the volume of the slab:

Volume of water displaced = Volume of the slab Volume of water displaced = 4 m³

The buoyant force can be calculated using the density of water and the acceleration due to gravity:

Buoyant force = density of water × volume of water displaced × acceleration due to gravity Buoyant force = 1000 kg/m³ × 4 m³ × 9.8 m/s² Buoyant force = 39,200 N

Conclusion

To summarize, the weight of the concrete slab in water is 94,080 Newtons and the buoyant force acting on the slab is 39,200 Newtons.

Please note that the values provided are based on the assumptions made regarding the density of concrete and water. The actual values may vary depending on the specific properties of the materials involved.