1.
What is NOT one of the four aerodynamic forces?
Correct Answer
B. Pressure
Explanation
Pressure is not considered one of the four aerodynamic forces because it is not a force that acts on an object in motion through a fluid. The four aerodynamic forces are lift, drag, thrust, and weight. Lift is the force that acts perpendicular to the direction of motion and allows an object to overcome gravity. Drag is the force that opposes the motion of an object through a fluid. Thrust is the force that propels an object forward. Weight is the force of gravity acting on an object. Pressure, on the other hand, is a measure of the force exerted by a fluid per unit area and does not directly contribute to the motion of an object through a fluid.
2.
Which aerodynamic force is known as "the resistance of air"?
Correct Answer
D. Drag
Explanation
Drag is the aerodynamic force that is known as "the resistance of air." It is the force that opposes the motion of an object through a fluid, such as air. Drag is caused by the interaction between the object and the air molecules, resulting in a force that acts in the opposite direction of the object's motion. It is an important force to consider in various applications, such as designing vehicles and aircraft, as it affects their speed, efficiency, and performance.
3.
What is a "natural" force acting upon the airplane?
Correct Answer
A. Weight/Gravity
Explanation
Weight/Gravity is considered a "natural" force acting upon the airplane because it is an inherent force of nature that affects all objects with mass. In the case of an airplane, weight is the force exerted by gravity on the aircraft due to its mass. This force acts vertically downwards and must be counteracted by other forces, such as lift, in order to maintain level flight or achieve controlled maneuvers. Therefore, weight/gravity is a fundamental force that plays a crucial role in the flight dynamics of an airplane.
4.
Who were the brothers that invented the airplane?
Correct Answer
C. Orville and Wilbur Wright
Explanation
Orville and Wilbur Wright were the brothers who invented the airplane. They were pioneers in aviation and made significant contributions to the development of powered flight. The Wright brothers successfully designed, built, and flew the world's first successful airplane, the Wright Flyer, in 1903. Their invention revolutionized transportation and had a profound impact on the world, leading to the advancement of aviation technology and the modern aviation industry.
5.
Which principle explains how an airplane flies?
Correct Answer
A. Bernoulli's Principal
Explanation
Bernoulli's principle explains how an airplane flies. According to this principle, as the speed of a fluid (such as air) increases, its pressure decreases. In the case of an airplane, the shape of the wings and the angle at which they are tilted generate a difference in air pressure above and below the wings. This pressure difference creates lift, allowing the airplane to overcome gravity and stay airborne.
6.
Which part of the airplane creates the lift?
Correct Answer
D. The Wings
Explanation
The wings of an airplane create lift. Lift is the force that allows an airplane to overcome gravity and stay in the air. The shape of the wings and the flow of air over them generate lift. As the airplane moves forward, air flows faster over the curved upper surface of the wing, creating lower pressure above the wing compared to the higher pressure below. This pressure difference creates an upward force called lift, which allows the airplane to fly. The other options mentioned, such as the pilot, propeller, and rudder, are important components of an airplane but do not directly create lift.
7.
What force must be created by an airplane, in order to overcome drag?
Correct Answer
A. Thrust
Explanation
In order for an airplane to overcome drag, it must generate a force called thrust. Thrust is the force that propels the airplane forward and counteracts the drag force that acts opposite to the direction of motion. This force is created by the engines of the airplane, which generate a powerful stream of exhaust gases that propel the aircraft forward. By generating enough thrust, the airplane can overcome the drag force and maintain its forward motion.
8.
Which part of the airplane provides thrust?
Correct Answer
C. Propellers
Explanation
Propellers provide thrust to the airplane. They are rotating blades that convert the engine's power into forward motion, pushing the aircraft through the air. The propellers generate a force called thrust, which propels the airplane forward and allows it to overcome drag and move through the air. Wings provide lift, rudder controls the direction of the aircraft, and flaps help with control and stability during takeoff and landing. However, it is the propellers that specifically generate the thrust required for the airplane to move forward.
9.
What are the primary flight controls for an aircraft?
Correct Answer
D. Elevator, rudder, ailerons
Explanation
The primary flight controls for an aircraft are the elevator, rudder, and ailerons. The elevator controls the pitch or the up and down movement of the aircraft, the rudder controls the yaw or the left and right movement of the aircraft, and the ailerons control the roll or the tilting movement of the aircraft. These three controls are essential for maneuvering and controlling the aircraft during flight.
10.
Drag for an aircraft comes in two varieties, parasitic and induced.
Correct Answer
A. True
Explanation
Drag for an aircraft comes in two varieties, parasitic and induced. This statement is true. Parasitic drag is caused by the friction between the aircraft's surface and the air, as well as the turbulence created by the aircraft's shape. Induced drag, on the other hand, is caused by the generation of lift and the creation of vortices at the wingtips. These two types of drag are important factors that need to be considered in aircraft design and operation.