How a submarine works

 1.Diving and Surfacing (Ballast System)

Submarines control their depth using ballast tanks.

To dive:

The tanks fill with water, making the submarine heavier, so it sinks.

To rise (surface):

The tanks are filled with compressed air, pushing the water out, making the submarine lighter, so it floats up.

Principle used: Buoyancy (Archimedes’ Principle)

2. Moving Forward (Propulsion System)

Submarines use propellers powered by engines.

Diesel-electric submarines:

Use diesel engines on the surface and electric batteries underwater.

Nuclear submarines:

Use nuclear reactors to produce heat → steam → electricity → movement.

This allows them to travel very fast and for months without refueling.

3. Steering and Control (Fins & Rudders)

Submarines use:

Rudders – turn left or right

Hydroplanes (fins) – move up or down underwater

These help in precise underwater navigation.

4. Breathing Underwater (Air System)

Submarines don’t take in outside air when underwater.

They:

Recycle oxygen

Remove carbon dioxide

Produce oxygen using electrolysis of water (splitting water into oxygen and hydrogen)

5. Seeing Underwater (Sonar System)

Since light doesn’t travel far underwater, submarines use SONAR:

Sends out sound waves

Listens to echoes to detect ships, submarines, and obstacles

6. Pressure Resistance (Strong Hull)

Deep underwater, pressure is extremely high.

Submarines are built with:

Thick, round steel hulls

Strong materials to prevent crushing