Science
How do submarines work?
A submarine works by changing how much it weighs compared to the water it displaces. To dive, it floods special tanks with water to get heavier; to surface, it pushes that water out with compressed air to get lighter.
See it in motion.
Watch a 2-minute animated lesson that shows exactly how submarines works.
Step by step
- 1Ballast tanks fill with water to make the sub dive.
- 2Compressed air pushes water out to make it rise.
- 3This controls buoyancy — whether it sinks or floats.
- 4Propellers and fins steer and drive it through the water.
Frequently asked questions
- How does a submarine dive and surface?
- It floods ballast tanks with water to sink and blows them out with compressed air to rise.
- What is buoyancy?
- The upward force water exerts on an object; controlling it lets a sub float, hover, or sink.
- How do submarines navigate underwater?
- They use sonar, since light doesn't travel far underwater, to sense their surroundings.