7 Flight Mystery and Aerodynamic Principles
461
Fig. 7.19 Principle of force balance—Chinese steelyard balance
blade of the bamboo dragonfly and the horizontal rotating surface. When
the impeller rotates, the rotating blade discharges the airflow from the upper
side to the lower side, that is, gives the air a downward thrust, thereby causing
the air to also act on the rotating blade with an upward reaction force, i.e.,
461
Fig. 7.19 Principle of force balance—Chinese steelyard balance
blade of the bamboo dragonfly and the horizontal rotating surface. When
the impeller rotates, the rotating blade discharges the airflow from the upper
side to the lower side, that is, gives the air a downward thrust, thereby causing
the air to also act on the rotating blade with an upward reaction force, i.e.,