Wind tunnel

A wind tunnel is a machine that creates a strong current of air that can be used to test the performance of things. It works by blowing air with a fan to create a wind-like environment inside a long tube. The items that are being tested are placed in the middle of the tube and the wind helps to show how the item will move and perform in different conditions. It is used to test the performance of cars, spacecrafts and aircrafts before they are sent into real life situations.