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Homework Help: Downward, find airtime, velocity

  1. Jun 11, 2005 #1
    water ballon thrown down at 15m/s to ground 25 m below, what is air time and velocity at impact
    y = y(i) + v(i)sint + 1/2gt2
    y = 25 + 15sin(90)t + 1/2(-9.8)t2 ? ?
     
  2. jcsd
  3. Jun 12, 2005 #2
    dude, try to understand the physics before pluging in numbers into a meaningless equation...read the book first...
     
  4. Jun 12, 2005 #3

    HallsofIvy

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    1. What does "air time" MEAN?
    2. More specifically, what ends the "air time"?
    3. What is y when the "air time" ends?
    4. No, not "y = y(i) + v(i)sint + 1/2gt2 "
    5. Do you know what sin(90) is?

    6. You need to solve an equation to find the time t when "air time" ends.
     
  5. Jun 12, 2005 #4
    first of all, g is not -9.8. you throw it downwards, not upwards
     
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