Question

U-tube is partly filled with water. Oil is then poured on top of the water on the left side of the tube. The final water levels on both sides are as shown. The...

a) Pressure difference increases
b) Pressure difference decreases
c) Pressure difference remains unchanged
d) Pressure difference is indeterminate

Answer 1

The pressure difference remains unchanged.

Step-by-step explanation:

The pressure difference remains unchanged.

In a U-tube, the pressure at points at the same height on the two sides of the tube must be the same as long as the two points are in the same liquid. Therefore, the pressure at the interface between the water and oil on the left side of the tube is the same as the pressure at the same level in the water on the right side of the tube. This means that the pressure difference between the two sides remains constant.