A submarine dives from the surface to 100 meters. How does the water pressure on the submarine change?

Hydrostatic pressure: Water pressure increases with depth because of the weight of water above.

Rule of thumb: Pressure increases by approximately 1 atmosphere (atm) or 14.7 psi for every 10 metres (33 feet) of seawater depth. At the surface: 1 atm (atmospheric pressure). At 10 m: 2 atm total. At 100 m: ~11 atm total. At 100 m, the submarine's hull experiences approximately 10× the pressure compared to the surface. Deep ocean trenches (10,000 m+) have pressures exceeding 1,000 atm. This is why submarines have thick pressure hulls and why scuba divers must manage nitrogen narcosis and decompression at depth.