SECTION 3 · 10 LESSONS

Underwater science

Explore the physical ideas behind pressure, buoyancy and the underwater environment.

Start with lesson one

Your ten lessons

Each lesson includes an illustration, a visual explanation, a reference table and a knowledge check. Work through them in order or revisit a question.

  1. 01

    Pressure and depth

    Explain why pressure changes below the surface.

  2. 02

    Gas volume and pressure

    Recognise the ideal relationship between gas volume and pressure.

  3. 03

    Buoyancy as a force

    Describe positive, negative and neutral buoyancy.

  4. 04

    Saltwater and freshwater

    Connect water density with buoyant force.

  5. 05

    Trim and body position

    Distinguish orientation from overall buoyancy.

  6. 06

    Light and colour underwater

    Understand why underwater colour and brightness change.

  7. 07

    Sound underwater

    Recognise that sound behaves differently in water.

  8. 08

    Heat and comfort

    Understand why exposure protection is part of planning.

  9. 09

    Breathing gases are not interchangeable

    Recognise why a gas name implies training and limits.

  10. 10

    Models, measurements and limits

    Distinguish a model from a direct measurement.