What defines the geometric pitch of a propeller?

The geometric pitch of a propeller is defined as the distance it would theoretically move forward in one complete revolution at the given blade angle, assuming there is no slip. This concept is critical in understanding how propellers generate thrust. The geometric pitch essentially describes the ideal forward motion of the propeller based on the design of the blades and their angle to the plane of rotation. This distance helps in determining the efficiency and performance of the propeller in converting engine power into forward thrust.

While other options mention various important characteristics of propeller design and aerodynamics, they do not accurately define geometric pitch. The angle of the propeller chord to the plane of rotation or to the relative airflow describes the propeller's aerodynamic characteristics but does not directly relate to the concept of pitch. Similarly, the actual distance the propeller moves forward in one revolution accounts for factors like slip, which is not relevant to the geometric pitch. Thus, the provided choice effectively captures the essence of what geometric pitch represents in propeller design.