Which statement correctly relates to the lift coefficient?

• A. The boundary between air masses.
• B. The ratio between lift pressure and dynamic pressure.
• C. A compass course.
• D. An IFR clearance.

Answer: (B)

Lift coefficient measures how effectively a wing converts the energy of the airflow into lift for a given wing size and flight condition. It’s defined through the relation L = q S CL, where L is lift, q is dynamic pressure (0.5 ρ V^2), and S is the reference wing area. From this, CL = L / (q S). So CL is a dimensionless ratio that expresses lift relative to the dynamic pressure acting on the wing, normalized by the wing area. This is why the statement describing a ratio between lift (per area) and dynamic pressure (and scaled by area) best captures what the lift coefficient is. The other options point to a weather front, a compass course, or an IFR clearance—none of which relate to how lift is quantified.