Where does the wind from the electric fan come from?
At the same time, the air velocity of the diagonal line must be faster than that of the straight line, causing the air pressure on both sides to vary. The air flowing along the straight line flows to the side of the air where the wind is formed
The air passes through the fan blade, because it is oblique, and when the air passes, the fan leaves the air straight, while the other side takes a diagonal line with the blade
The Bernoulli principle. Just like an airplane has wings,
