Understanding the Forces Affecting Helicopter Motion

What forces affect the motion of a helicopter and why?

Choose from one of the following options:

a) Air pushing upward affects the helicopter's motion because it is an internal force that acts on the helicopter.

b) Air pushing upward affects the helicopter's motion because it is an external force that acts on the helicopter.

c) The downward force applied by the blades of the helicopter affects its motion because it is an internal force that acts on the helicopter.

d) The downward force applied by the blades of the helicopter affects its motion because it is an external force that acts on the helicopter.

Final answer:

The motion of a helicopter is affected by the upward force of the air, an external force caused by the helicopter blades pushing air downwards. This works on the basis of Newton's Third Law of Motion, where every action has an equal and opposite reaction.

The force that affects the helicopter's motion is the reaction force of the air pushing upward, which is an external force. This is in line with Newton's Third Law of Motion, stating that for every action, there is an equal and opposite reaction. Hence, when the helicopter blades push air downwards (an internal force), the air pushes back upwards on the helicopter (an external force), allowing it to rise or stay aloft. The force exerted by the helicopter's blades is internal because it originates from within the system.

In other examples, birds and airplanes also exert force on the air in a direction opposite the direction they wish to move. The wings of a bird, for example, force air downward and backward to achieve lift and move forward.

Beyond helicopters and airplanes, this reaction force concept can also be observed in other scenarios like a baseball pushed forward by a bat, an octopus jetting water backward to move forward, or a rocket expelling gas backward to travel forward. These all work on the universal principle of Newton's Third Law of Motion.

How do external and internal forces contribute to a helicopter's motion?

Choose from one of the following options:

a) External forces like lift and internal forces from the engine work together to propel the helicopter.

b) Only external forces like lift are responsible for the helicopter's motion.

c) Internal forces from the engine are the sole drivers of the helicopter's motion.

d) Internal and external forces do not play a role in a helicopter's motion.

Final answer:

The helicopter's motion is affected by both external forces (air pushing upwards) and internal forces (blades pushing air downwards). The external force creates lift, enabling the helicopter to ascend or maintain altitude, while the internal force from the engine spins the blades. Additional stabilizing forces from the tail rotor counter torque caused by the main rotor.

The motion of a helicopter is influenced by two main forces. The external force creates lift that allows the helicopter to ascend or remain in flight, while the internal force from the engine drives the rotation of the blades, contributing to the helicopter's motion.

Without external stabilizing forces like the tail rotor to counter any torque from the main rotor, the helicopter would experience unwanted spinning due to the conservation of angular momentum.

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