Question

Найдите вес полого медного шара, если радиус шара 10 см, а толщина стенок 1 см.

Answer 1

m = pV, где р = 8930 кг/м^3 - плотность меди.   Найдем объем V:

Объем шаровой оболочки: V = (4П/3)(R1^3  -  R2^3), где R1 = 10 cm, R2=9 cm.

Тогда масса шара:

m = (4Пp/3)(R1^3 - R2^3)= 4*3,14*8930*(10^(-3) - 0,73*10^(-3))/3 = 10 кг

Вес покоящегося шара: P=mg=100 Н  (10 кГ)

Answer 2

Calculation of the Weight of a Hollow Copper Sphere

To find the weight of a hollow copper sphere, we need to calculate the volume of the hollow space and subtract it from the volume of the entire sphere. Then, we can multiply the resulting volume by the density of copper to find the weight.

Given: - Radius of the sphere (r) = 10 cm - Thickness of the walls (t) = 1 cm

Calculating the Volume of the Hollow Space

The volume of the hollow space can be calculated by subtracting the volume of the inner sphere from the volume of the outer sphere.

The volume of the outer sphere is given by the formula: V_outer = (4/3) * π * (r + t)^3 The volume of the inner sphere is given by the formula: V_inner = (4/3) * π * r^3 Substituting the given values into the formulas, we can calculate the volumes:

V_outer = (4/3) * π * (10 + 1)^3 = (4/3) * π * 11^3 V_inner = (4/3) * π * 10^3

Calculating the Weight of the Hollow Copper Sphere

The weight of the hollow copper sphere can be calculated by subtracting the volume of the hollow space from the volume of the entire sphere and then multiplying it by the density of copper.

The density of copper is typically around 8.96 g/cm³.

The weight (W) can be calculated using the formula: W = (V_outer - V_inner) * density

Substituting the calculated volumes and the density of copper into the formula, we can calculate the weight:

W = ((4/3) * π * 11^3 - (4/3) * π * 10^3) * 8.96

Now, we can calculate the weight of the hollow copper sphere using the given values:

W = ((4/3) * π * 11^3 - (4/3) * π * 10^3) * 8.96

Please note that the weight will be in grams (g) since the density is given in grams per cubic centimeter (g/cm³).