Question

В U-образной трубке налита нефть и вода. Высота столба нефти 10 см. насколько высота столба воды ниже, чем нефти?

Answer 1

P1*g*h1=p2*g*h2
h2=p1*g*h1/p2*g=800*10*10/1000*10=8 см
h1-h2=10-8=2 см

Answer 2

Calculating the Height of the Water Column

To calculate the height of the water column in a U-shaped tube filled with oil and water, we can use the principle of communicating vessels. The pressure at any given point in a fluid at rest is the same at all points of the same height. This means that the pressure at the same height in the oil and water columns is the same.

According to the principle of communicating vessels, the heights of the oil and water columns are inversely proportional to the densities of the liquids. The formula for this relationship is:

h_o / h_w = ρ_w / ρ_o

Where: - h_o = height of the oil column - h_w = height of the water column - ρ_w = density of water - ρ_o = density of oil

Applying the Formula

Given that the height of the oil column is 10 cm, we can use the above formula to find the height of the water column.

Using the densities of water and oil, which are approximately 1 g/cm³ and 0.8 g/cm³ respectively, we can calculate the height of the water column.

h_w = (ρ_o * h_o) / ρ_w

h_w = (0.8 * 10) / 1

h_w = 8 cm

Conclusion

Therefore, the height of the water column in the U-shaped tube is 8 cm lower than the height of the oil column.