The Final Showdown Was Here!

Anyone who's been blown up by a torpedo should know this.

Torpedoes are different from ordinary missiles. The principles behind how they work are actually very complex.

It still has to do with the incompressibility of water.

As everyone knows,

most ammunition contains explosives. When explosives detonate, they produce a large amount of high-temperature, high-pressure gas in a very short time.

The gas expands rapidly, and the energy of that expansion is what gives some weapons their destructive power.

For a high-explosive round, the expanding gas shatters the casing into a mass of high-speed fragments, whose kinetic energy causes the damage.

For an armor-piercing round, the expanding gas compresses a metal liner into a high-temperature, high-speed jet that penetrates armor.

When gas expands in air, which is compressible, some of its energy is spent compressing the air before it can surge outward and form a shock wave.

But water is five orders of magnitude less compressible than air. So the energy from the expanding gas doesn't need to compress the water; it can surge straight through and form a shock wave.

This is what torpedo design calls "shock energy."

Underwater, the energy of the expanding gas turns water into bubbles, and the bubbles expand.

Because of inertia,

the bubbles don't stop expanding when the pressure inside them matches the pressure of the surrounding water. They keep growing.

That leaves the pressure inside the bubbles lower than the water pressure, so the water rushes back in and compresses them.

Again, because of inertia, the bubbles don't stop when their internal pressure matches the surrounding water pressure. They keep getting compressed.

Then the pressure inside the bubbles becomes greater than the pressure outside, so they expand again. This cycle repeats until the pressure inside and outside finally balances. In underwater explosion theory,