1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Diving hawks.

  1. Aug 11, 2007 #1
    3. When the Sun is directly overhead, a hawk dives toward the ground with a constant velocity of 5.00 m/s at 60.0 degrees below the horizontal. Calculate the speed of her shadow on the level ground.

    I am having some trouble picturing this problem in terms of a coordinate grid (this is in a chapter dealing with motion in two dimensions). I'm basically making a triangle, and I know (or at least I'm hoping) that the shadow is the horizontal component of the vector that is the hawk's flight. If it's 60 degrees below the "horizontal" or, the way I see it, the "line of sight", the direction is equivalent to 300 degrees if making an imaginary coordinate grid at the point before she descends, making the h.c. = 5.00cos300. Or, actually, the entire thing is a 30-60-90 triangle, so the velocity of her shadow is 2.5 m/s.

    ...is that right? Or, rather, is my long-winded train of thought correct?
  2. jcsd
  3. Aug 11, 2007 #2


    User Avatar
    Homework Helper
    Gold Member

    Your answer is correct. Good Job!

    You should get the same answer if you did the problem with the cosine of 300 degrees or with the 30-60-90 triangle. Both descriptions of the situation can accurately be used to find the answer.

    Also, your thinking, as far as I understand it, is correct. 60 degrees below the horizontal in the can be described by an angle of 300 degrees. Was this all you were asking or is there more to your train of thought that you were unsure about?
    Last edited: Aug 11, 2007
  4. Aug 11, 2007 #3
    Yes you are right
  5. Aug 12, 2007 #4
    Thank you! :DDD

    That was all I was wondering.
  6. Aug 12, 2007 #5
    Yep, yep!

    Thanks a bunch! =]
  7. Oct 20, 2008 #6
    ok can someone plz explain how the picture looks for this question!
    i dont understand the picture since it says the hawk is diving down under the horizontal
    so where is the shadow?
    help plz
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Similar Discussions: Diving hawks.
  1. Diving board (Replies: 7)

  2. Sky diving (Replies: 2)

  3. Diving bell (Replies: 5)