Lift-to-drag ratio

When something flies, we want it to go the furthest possible distance with the least amount of energy. The lift-to-drag ratio helps us measure how well things can do this. It is the amount of lift force that keeps something in the air, divided by the amount of drag force that holds that something back.

When we throw something like a paper airplane, it can stay in the air for a certain amount of time because of its lift-to-drag ratio. The lift force comes from the air pushing up on the wings, while the drag force is the air pushing against the front of the airplane.

If the lift force is stronger than the drag force, then the lift-to-drag ratio is high and the object will fly for a long time. But if the drag force is stronger than the lift force, then the lift-to-drag ratio is low and the object won't fly very far.

A high lift-to-drag ratio means that things like airplanes and birds can fly for longer periods of time while using less energy, which is important for long distance flights. Scientists and engineers work to design planes with high lift-to-drag ratios, so that they can be more efficient and travel further.