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Homework Help: Where u and v and initial and final velocities

  1. Oct 18, 2003 #1
    Hey
    Looking for some help with another projectiles question:

    Ok, so for part (A) ive made this sketch:

    http://community.webshots.com/s/image1/4/51/1/95445101CnvHBl_ph.jpg

    Ux = 47.04
    Uy = 19.6
    Vx = 47.04
    Vy = 19.6 - gt
    Ax = 0
    Ay = -g
    Sx = 47.04t
    Sy = 19.6t - 1/2gt^2

    where u and v and initial and final velocities, and a and s are acceleration and distance, x and y are in the horizontal and vertical directions.

    I subbed in Sy = 14.7 and got a quadratic with two solutions - t=1 and t=3, since the time of flight is 8 seconds, either solution is acceptable.
    Im stuck as to what to do next. Any hep would be appreciated.

    (B) Heres my sketch for this part:
    http://community.webshots.com/s/image1/4/49/1/95444901reiLfQ_ph.jpg

    Im totally stuck here. The given velocity is what i would have thought to be the x velocity, suggesting the particle has no y velocity - which cant be possible i think? Any help as to how to break this down would be helpful
     
    Last edited by a moderator: Feb 6, 2013
  2. jcsd
  3. Oct 19, 2003 #2
    Any help is appreciated
     
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