How about a timestamp given it's a long lecture?Wing 11 said:but he claims
41:00 - 47:00 minA.T. said:How about a timestamp given it's a long lecture?
He doesn't say that. He just says that the downward momentum doesn't accumulate in the atmosphere as a whole. The increased reaction from the ground cancels it.Wing 11 said:but he claims that downward air flow "downwash" do not exist
The theory of lift states that an object, such as an airplane wing, can generate an upward force when it moves through a fluid, such as air. This is due to the difference in air pressure above and below the wing, which creates a lift force that can counteract the weight of the object and allow it to fly.
The shape of an object, particularly its airfoil shape, can greatly affect the amount of lift it can generate. A curved or cambered shape on the top of the object can create a longer path for the air to travel over, resulting in lower air pressure and more lift. Additionally, the angle of attack, or the angle at which the object meets the fluid, can also impact lift.
Bernoulli's principle states that as the speed of a fluid increases, its pressure decreases. This is often used to explain lift by stating that the air moving over the curved top of an airfoil must travel faster, creating lower pressure and resulting in lift. However, Newton's third law, which states that for every action there is an equal and opposite reaction, also plays a role in lift. The downward force of the air pushing on the wing creates an equal and opposite force of lift on the wing.
No, lift cannot be produced in a vacuum as there is no fluid for the object to move through and create a pressure difference. However, in space, objects can still move and change direction using thrusters and other mechanisms that do not rely on lift.
The lift force can be calculated using the lift equation, which takes into account the air density, air speed, wing area, and lift coefficient. The lift coefficient is a dimensionless number that takes into account the shape and angle of attack of the object. By multiplying these factors together, one can determine the amount of lift force acting on an object.