ASVAB (Armed Services Vocational Aptitude Battery)Mechanical Comprehension (MC)Easy
A diver is swimming underwater. As the diver descends deeper, the pressure exerted by the water increases. This increase in pressure is primarily due to which factor?
- AThe density of the water decreasing.
- BThe increasing weight of the water column above the diver.
- CThe kinetic energy of the water molecules increasing.
- DThe volume of the diver's body increasing.
Show answer & explanationAnswer & explanation
Correct answer: B. The increasing weight of the water column above the diver.
Hydrostatic pressure in a fluid increases with depth. This is because as a diver goes deeper, the column of water above them becomes taller, meaning there is more weight of water pressing down from above, leading to a greater pressure.
Why the other options are wrong
- A. The density of water remains relatively constant, or slightly increases, with depth, not decreases.
- C. Kinetic energy of water molecules relates to temperature, not directly to the pressure increase with depth.
- D. The volume of the diver's body does not significantly change with depth in a way that causes pressure increase.
Hydrostatic Pressure
The pressure exerted by a fluid at rest due to the force of gravity. It increases with depth because the weight of the fluid column above a point increases.
- Increases linearly with depth.
- Depends on fluid density and gravity (P = ρgh).
- Acts equally in all directions at a given depth.
Memory trick: Deeper you dive, more 'weight' of water 'presses' from 'above'.