Question

Воздушный шарик, наполненный гелием, поднялся на высоту третьего этажа. Объём шарика равен 1 л, высота одного этажа — 2,5 м. Определи в мДж, какую работу совершила выталкивающая сила.

Answer 1

Ответ:

дано. Си

0,001м³

V-1л

h=2,5м

----------------

Fa(сила Архимеда)-?

А-?

решение

А=F×h, F=P(плотность)×g×V

Fa=0,178кг/м³ × 10 Н/кг × 0,001м³= 0,00178Н

А= 0,00178Н ×2,5м = 0,00445мДж

Answer 2

Calculation of the Work Done by the Buoyant Force

To calculate the work done by the buoyant force, we need to determine the distance over which the force acts. In this case, the distance is the height that the balloon rises, which is equal to the height of the third floor.

Given: - Volume of the balloon: 1 L - Height of one floor: 2.5 m

To find the height that the balloon rises, we need to convert the volume of the balloon from liters to cubic meters. Since 1 L is equal to 0.001 cubic meters, the volume of the balloon is 0.001 m^3.

The buoyant force acting on the balloon is equal to the weight of the displaced air. According to Archimedes' principle, the buoyant force is equal to the weight of the fluid displaced by the object. In this case, the fluid is air.

The weight of the displaced air can be calculated using the formula:

Weight of displaced air = density of air x volume of displaced air x acceleration due to gravity

The density of air is approximately 1.225 kg/m^3, and the acceleration due to gravity is approximately 9.8 m/s^2.

Now we can calculate the weight of the displaced air:

Weight of displaced air = 1.225 kg/m^3 x 0.001 m^3 x 9.8 m/s^2

The work done by the buoyant force is equal to the product of the buoyant force and the distance over which it acts. In this case, the distance is the height of the third floor, which is 2.5 m.

Now we can calculate the work done by the buoyant force:

Work done = Weight of displaced air x height

Substituting the values:

Work done = (1.225 kg/m^3 x 0.001 m^3 x 9.8 m/s^2) x 2.5 m

Calculating the above expression gives us the work done by the buoyant force in joules (J).

Please note that the above calculation assumes ideal conditions and neglects factors such as air resistance and the weight of the balloon itself.