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Homework Help: New to the board. Can I get some guidance on a couple of questions?

  1. Jan 14, 2009 #1
    1. The problem statement, all variables and given/known data
    1) The drawing shows a person looking at a building on top of which an antenna is mounted. The horizontal distance between the person's eyes and the building is d = 68.0 m. In part a the person is looking at the base of the antenna, and his line of sight makes an angle of θ1 = 35.0° with the horizontal. In part b the person is looking at the top of the antenna, and his line of sight makes an angle of θ2 = 40.0° with the horizontal. How tall is the antenna?

    2) The two hot air balloons in the drawing are 48.2 and h = 56.0 m above the ground. A person in the left balloon observes that the right balloon is θ = 13.4° above the horizontal. What is the horizontal distance x between the two balloons?


    2. Relevant equations
    for the first i used cos and the second problem i used tan



    3. The attempt at a solution
    i got 57.1 km for the fist and 235 m for the second. but it says both are wrong
     
  2. jcsd
  3. Jan 14, 2009 #2
    ok i got #2 but still stuck on 1
     
  4. Jan 14, 2009 #3
    Let [tex]a[/tex] be the height of the base of the antenna off the ground

    Let [tex]b[/tex] be the height of the top of the antenna off the ground

    [tex]\tan35^{\circ} = \frac{a}{68.0}[/tex]

    [tex]\tan40^{\circ} = \frac{b}{68.0}[/tex]

    Now you have to solve for a and b and find [tex]b-a[/tex]
     
  5. Jan 14, 2009 #4
    thanks!
     
    Last edited: Jan 14, 2009
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