1/28/11

Post date: Jan 28, 2011 4:59:55 PM

Bell Ringer: Why do we have wind?

• • Paper plane directions

    • Write clear, step-by-step instruction to make your paper plane

    • Write these in 2nd person (do this, do that, NOT we did this, we did that)

    • Trade with another person and edit their instructions for spelling, grammar, and clarity

    • Make suggested changes to your directions

  • Answer the following question: How is pressure related to how your paper plane flies? Draw a diagram of your plane flying, and label areas of high pressure and low pressure around your plane.

    • Due Monday

  • How planes use pressure

    • Flight

      • Newton's 3rd law (to be discussed in the physics part of this class) explains part of how wings generate lift

      • Wings of a plane push air downward as the plane moves forward

      • Wings are shaped so that air will have very high pressure below the wing, and lower pressure above the wing.

      • Air moves from high to low pressure (up), and takes plane up with it.

    • In the cabin

      • Planes go very high, where air pressure is low

      • People have a hard time getting enough air when the pressure is that low

      • The inside of the cabin is kept at a higher air pressure than the surrounding air, to keep people comfortable

      • The structure of a plane must be VERY strong to hold all of this extra pressure inside the plane.