In a fluid at rest, the pressure at a point is primarily due to the weight of the fluid above that point. This describes which type of pressure?

• A. Nominal
• B. Specific
• C. Hydrostatic
• D. Absolute

Answer: (C)

Hydrostatic pressure is the pressure in a fluid at rest that arises from the weight of the fluid above a point. As you go deeper (increase depth h), the weight of the overlying fluid adds more pressure, giving p = ρ g h for the contribution from the fluid itself. In open surroundings, the surface is exposed to atmospheric pressure, so the total (absolute) pressure at depth is p_abs = p_atm + ρ g h, but the part described by “weight of the fluid above” is the hydrostatic component. This is why the described situation fits hydrostatic pressure best.