In a u-tube as shown in the fig. water and oil are in the left side and right side of the tube respectively. The heights from the bottom for water and oil columns are 15 cm and 20 cm respectively. The density of the oil is [take ρ_water = 1000 kg/m³]

CONCEPT:

The pressure of the static fluid is defined as the product of the depth of the fluid, the density of the fluid, and acceleration due to gravity we have;

P = hdg

Here we have h is the height, d is the density and g is the acceleration due to gravity

CALCULATION:

Given: ρ_water = 1000 kg/m³ , hwater = 15 cm and hoil = 20 cm

As in the given question, the pressure of the oil = the pressure of the water and it is written as;

ρoilhoil = ρwaterhwater 

\(\Rightarrow ρ_{oil} = \frac {ρ_{water} h_{water} }{ h_{oil}}\)    ----(1)

Now, on putting the given values in equation (1) we have;

\(\Rightarrow ρ_{oil} = \frac {1000 \times 15 }{ 20 }\)

⇒ρ_oil = 750 kg/m³

Hence, option 4) is the correct answer.