What are the two types of parasite drag?

Parasite drag is a crucial concept in aerodynamics, representing the drag that does not contribute to lift. It consists primarily of two components: form drag and skin friction drag.

Form drag arises from the shape of an object as it moves through a fluid, such as air. This drag is generated due to the pressure differential between the front and rear of the object. An aerodynamically shaped object will experience less form drag than a bulky or poorly shaped one because it allows the air to flow smoothly around it, reducing turbulence.

Skin friction drag, on the other hand, is caused by the interaction of the air with the surface of the object. It is a result of the viscosity of the air and the roughness of the surface. As air flows over the surface, it clings to it due to friction, thus creating additional resistance. A smooth surface will have less skin friction drag than a rough one, as a smoother surface allows for a more streamlined flow.

Therefore, the response accurately identifies form drag and skin friction drag as the two main types of parasite drag, highlighting how both contribute to the overall drag experienced by an object in motion through a fluid environment.