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Homework Help: Circular Motion and Newton's Laws

  1. Mar 19, 2008 #1
    A model airplane of mass 7.50 with a speed 35m/s flies in a horizontal circle at the end of 60.0m control wire. Aerodynamic lift acts on the plane at an angle of 20 degrees West of North.

    In the picture the book has the plane on the right. The weight is acting straight down, the tension is acting at angle of 20 degrees South of East and the aerodynamic lift is acting 20 degrees west of north.

    Can someone set up the x and y scalar equations please. The answer is 12.8N. I have set it up 5 different ways and i can't seem to get the right answer.
  2. jcsd
  3. Mar 19, 2008 #2
    You should show some work and post it in the homework help section next time. Now if you'll excuse me, I gotta jet.

  4. Mar 19, 2008 #3
    Looks like this was moved to homework help, but rmarkatos had already posted there.

    May be best to continue in the other thread.
  5. Mar 19, 2008 #4
    Fx -Tcos20 - Fsin20 = mv^2/r
    Fy -Tsin20 + Fcos20 - mg = 0 where T is the tension and F is the aerodynamic lift

    Those are the equations based on the picture described.
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