Interplanetary Postal Service is a simple, but addictive spaceship game built with a goal to simply explain the physical effect of fluid dynamics and illustrate forces that arise by the flow. The game belongs under educational games for physics.

Fluid dynamics | Interplanetary Postal Service game is composed of 8 missions within which player's goal is to deliver a mailpiece on the ramp located in an inaccessible place. For successful playing, a player must take into account forces acting on the ship, such as gravity, fluid dznamics as well as positional and kinetic energy resulting from the position and movement of the ship.

What does Fluid Dynamics mean? <q cite=„https://en.wikipedia.org/wiki/Fluid_dynamics“>Fluid dynamics is a subdiscipline of fluid mechanics that describes the flow of fluids—liquids and gases.</q>

What forces you can expect in the game:
1) Gravitation Simple explanation:
Gravity is a force that makes all forms of matter attract each other. The magnitude of the gravitational force is proportional to the mass of the bodies between which it acts. The best known gravitational effect is the gravitational effect of planets and stars. Thanks to this effect the Earth orbits the Sun and it is easy to walk on Earth.
In controlling the ship, gravity must be taken into account as the force that draws the ship to the ground and thus increases its descent speed (conversion of positional energy into kinetic) .

Interesting fact The Law of Gravity was formulated by Isaac Newton and is known as the 4th Newton's Law. The first three are all known laws:

Law of Inertia
Law of Power
Act of Action and Reaction

External forces due to fluid

The acting fluid (gas) on the outer surface of the ship transmits a portion of its kinetic energy to the ship, which causes the ship to be carried in the direction of flow of the fluid, if this force is higher than forces from air friction acting in the opposite direction.

Engine forces

These are the forces that make it possible to control the ship's flight, provided these forces are higher than the surrounding forces acting on the ship.

The Game Fluid Dynamics was developed by S-macke for js13kgames competition and is available as Open Source.