Air
Fast-moving air above a wing and slower air below it create this.
What is lift?
The force that comes from engines or propellers.
What is thrust?
What are two ways in which thrust can be created?
by an engine or by a propeller
Energy resources that can be replaced naturally.
What are renewable energy resources?
Describe one experiment to prove that air pressure exists.
1) Index card on the glass of water - the air pressure on the outside of the glass was greater; it pushed upward on the card making it stay up 2) We blow outwards on our cheeks without opening our lips - we could feel the air pressure pushing on the inside of our cheeks 3)inflated tyre shows air has pressure
This happens to air pressure when air moves faster.
What is lower pressure?
The force caused by air resistance.
What is drag?
When thrust equals drag and lift equals gravity, the airplane is ____.
What is flying at a constant speed and altitude?
Name 4 renewable energy resources.
What is wind / solar / water / biomass?
How is heat in air related to its density
hot air is less dense,while cold air ismore dense
Air always moves from this type of pressure to this type of pressure.
What is high pressure to low pressure?
The force created by differences in air pressure.
What is lift?
In order for a plane to remain in a forward motion, the _________ must be greater than the _____________.
thrust, drag
Name two non-renewable energy resources.
What is fossil fuels and nuclear?
Which force should be greater to let hot air balloon move upwards______, Move downwards_______
Lift, weight
This principle explains why fast-moving air has lower pressure.
What is Bernoulli’s Principle?
If air is moving faster above a wing than below it, the pressure above the wing will be ____.
What is lower?
In order for a plane to remain up in the air, the ________ must be greater than the __________.
lift, gravity
Explain why hydroelectric power is renewable but can still have environmental impacts.
What is it uses water that is replaced, but dams can affect habitats and rivers?
A helicopter is different from an airplane because of these reasons (name 3)..
1) Its propellers generate lift and thrust at the same time 2) it takes off directly from the ground instead of moving down a runway (less space needed to take off) 3) Because of its propellers, it can hover in one spot without moving forward 3) It can move forward, BACKWARD, up and down 4) It can travel at a lower altitude and more slowly than a plane (making it useful for many different activities)
Explain why air expands and rises when heated.
When air is heated its molecules move faster and spread farther apart - therefore it expands When the molecules spread farther apart they have less weight - therefore it rises
Explain why faster-moving air creates lower pressure.
What is because the air molecules spread out more and collide less often?
Explain Bernoulli's principle. How does the airfoil shape of a wing take advantage of this principle?
the faster air moves, the less pressure it exerts. Airfoil: is curved on the top - the air move faster; therefore it exerts less pressure. It is flat on the bottom - the air moves slower; therefore it exerts more pressure and results in LIFT.
Choose an energy resource and explain how availability or environmental impact affects its use.
What is a reasoned explanation (e.g., solar depends on sunlight; fossil fuels cause pollution)?
The best parachute would have the most ____, also called _____ __________.
drag, air resistance