The pressure in a static liquid increases with depth due to which cause?

• A. The weight of the overlying liquid
• B. Temperature differences
• C. Atmospheric pressure
• D. The level of agitation

Answer: (A)

In a still liquid, pressure rises with depth because the column of liquid above each point exerts its weight downward. This hydrostatic effect means every drop below supports all the liquid above it, so pressure increases linearly with depth. The standard expression is p = p0 + ρ g h, where p0 is the surface pressure, ρ is the density, g is gravity, and h is depth. The surface pressure sets the baseline, but the increase with depth comes from the weight of the overlying liquid.

Other factors like temperature differences, atmospheric pressure, or agitation don’t cause the depth-dependent rise in a static liquid. Temperature changes can affect density and motion, atmospheric pressure sets the starting pressure at the surface, and agitation would indicate motion rather than a static hydrostatic condition.