Newton's Third Law: Lift in Helicopters

What does the lift experienced by a helicopter involve?

1) helicopter blades and the air
2) mass of the helicopter and the earth's mass
3) weight of the helicopter and atmospheric pressure
4) motion of the helicopter relative to the ground
5) any or all of the above

Answer:

The lift experienced by a helicopter involves an action-reaction pair of forces between the helicopter blades and the air.

When a helicopter is in flight, the lift it experiences is a result of the interaction between the helicopter blades and the air. This interaction is in accordance with Newton's Third Law of motion, which states that every action has an equal and opposite reaction.

As the helicopter blades spin, they push the air downwards. This downward action on the air creates an upward reaction force on the helicopter blades, providing the lift necessary for the helicopter to stay airborne.

To prevent the helicopter from spinning uncontrollably, most helicopters are equipped with a tail propeller. The tail propeller helps counteract the torque produced by the main rotor blades, ensuring stable flight.

In certain cases, helicopters may have two sets of lifting blades rotating in opposite directions. This design helps balance out the torque and eliminates the need for a tail propeller.

Newton's Third Law also applies to other forms of flight, such as birds flying or rockets producing thrust. In each case, the principle of action and reaction governs the motion and stability of the flying object.