Discuss the action and reaction in the following cases. i) Hovering of a helicopter ii) Propulsion of a jet aeroplane

i) Hovering of a Helicopter:

The action in this case is the helicopter blades pushing air downwards. According to Newton's third law of motion, every action has an equal and opposite reaction. So, the reaction to this action is the air pushing the helicopter upwards. This upward force counteracts the force of gravity, allowing the helicopter to hover in the air.

ii) Propulsion of a Jet Airplane:

The action in this case is the jet engine sucking in air and expelling it out the back at high speed. The reaction, according to Newton's third law, is the forward thrust that propels the airplane forward. This is because the force exerted by the jet engine to push the air backwards results in an equal and opposite force that pushes the airplane forward.