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Airplanes vs. Rockets:
Airplanes vs. Rockets:
Airplanes vs. Rockets:
What are the principles of flight for planes and
rockets?
Principles of flight: airplanes
• What causes airplanes to fly?
Principles of flight: airplanes
• What causes airplanes to fly?
• Bernoulli’s Principle:
Principles of flight: airplanes
• What causes airplanes to fly?
• Bernoulli’s Principle: As the speed of a moving fluid increases, the pressure within the fluid decreases.
Principles of flight: airplanes
• What causes airplanes to fly?
• Bernoulli’s Principle: As the speed of a moving fluid increases, the pressure within the fluid decreases.– Faster flowing air has less pressure so an
object will be pushed in the direction of the fast moving air by the normal air pressure on the other side.
Principles of flight: airplanes
• Why does the air speed change?
Direction of travel for the plane
Principles of flight: airplanes
• Why does the air pressure change?
Principles of flight: airplanes
• Why does the air plane go up?
Principles of flight: Rockets
• Rockets do not use Bernoulli’s principle for take off.
Principles of flight: Rockets
• Rockets do not use Bernoulli’s principle for take off.
• Instead they utilize Newton’s Third Law.
Principles of flight: Rockets
• Rockets do not use Bernoulli’s principle for take off.
• Instead they utilize Newton’s Third Law.– Newton’s Third Law states that every action
has an equal and opposite reaction.
Principles of flight: Rockets
Principles of flight: Rockets
Principles of flight: Rockets in orbit
• What needs to happen to achieve orbit?
Principles of flight: Rockets in orbit
• What needs to happen to achieve orbit?
• To achieve and maintain an orbit there needs to be a balance between the force of gravity between the two objects and the orbiting object’s inertia.
Principles of flight: Rockets in orbit
• What needs to happen to achieve orbit?– Inertia (Newton’s 1st law): States that an
object at rest stays at rest and an object in motion stays in motion with the same speed and in the same direction unless acted upon by an outside force.
Principles of flight: Rockets in orbit
• What needs to happen to achieve orbit?– Inertia (Newton’s 1st law): States that an
object at rest stays at rest and an object in motion stays in motion with the same speed and in the same direction unless acted upon by an outside force.
– Increasing speed increases inertia.
Speed of rocket
Speed of rocket
Gravity
Speed of rocket
Gravity
If speed equals gravity you are in a constant orbit.
Speed of rocket
Speed of rocket
Gravity
Speed of rocket
GravityIf speed is less than Gravity you are in a
decaying orbit (crashing or landing).
Speed of rocket
Speed of rocket
Gravity
Speed of rocket
GravityIf speed is more than gravity you are leaving orbit (going
to the moon).
