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Homework Help: Impossible Questions NEED HELP!

  1. Oct 9, 2007 #1
    I really need help with these questions on my review sheet. I don't understand them and i have a test tommorrow. Can somebody show me how to do it, along with the answer. Do NOT answer in Significant Figures

    1. The problem statement, all variables and given/known data
    A truck travels beneath an airplane that is
    moving 150 km/h at an angle of 42 degrees to the
    a) How fast must the truck travel to stay
    beneath the airplane? Answer in units of
    b) What is the magnitude of the vertical com-
    ponent of the velocity of the plane? Answer
    in units of km/h.

    2. Relevant equations
    You could try to answer this one also its difficult. I have no idea how to do it.
    During the rodeo, a clown runs 13 m north,
    turns 28 degrees east of north, and runs 3.6 m. Then,
    after waiting for the bull to come near, the
    clown turns due east and runs 6.6 m to exit
    the arena.
    a) What is the magnitude of the clown's
    total displacement? Answer in units of m.
    b) How many degrees east of north is the
    clown's total displacement? Answer in units
    of degrees.

    3. The attempt at a solution
    I think its 114.9 for A and 96.8 for B

    Do NOT answer in Significant Figures
  2. jcsd
  3. Oct 9, 2007 #2


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    Staff Emeritus
    Science Advisor

    Alternatively, you could try to answer the questions!

    Forum rules state that you must show some work before we can help you. What have you tried?
  4. Oct 9, 2007 #3
    I've tried for hours to answer the questions......it seems impossible to do...I just need help! I'm new to the class, and my teacher isn't helping me much.
  5. Oct 9, 2007 #4


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    Staff Emeritus
    Science Advisor

    Well, could you perhaps post some of the work you've done thus far, and someone can point out errors in your reasoning. You must have some incling as to how to start. Have you covered any equations in class that you think may be relevant, for example?
  6. Oct 10, 2007 #5
    well just think about it, the plane is at an angle 42 degrees from the ground. The truck would have to travel as fast as the horizontal component of the planes velocity. Do you remember your basic trig? sin (x)= opp/ hyp and cos(x)=adj/hyp well now just imagine the triangle that the plane makes and what the adjacent and oppossite values are. all you need to solve the equation ive given (further hint : hyp= velocity of plane, 150 km/h)
  7. Oct 10, 2007 #6


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    Gold Member

    For the second, it will really help to draw a diagram that maps out the clowns motion. Have you done that?
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