Which term describes parasite drag caused by the object's shape and airflow around it?

• A. Skin friction drag
• B. Interference drag
• C. Form drag
• D. Induced drag

Answer: (C)

The main idea here is understanding how drag that comes from the shape of an object in a flow is classified. When air flows around a body, the shape determines how pressure builds up in front and how it recombines behind. This pressure distribution creates a resisting force opposite the motion, known as form drag (pressure drag). It specifically describes the drag caused by the object's form and the resulting airflow around it.

Skin friction drag, in contrast, comes from viscous shear on the surface itself, not primarily from the overall shape forcing pressure differences. Interference drag results from the way airflow is disturbed where different parts of a structure meet and interact. Induced drag is tied to the generation of lift and is a consequence of the energy put into creating lift, not just the shape of the body in smooth flow. Therefore, the term that best matches “parasite drag caused by the object's shape and airflow around it” is form drag.