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Homework Help: Projectile motion cannon shot

  1. Apr 27, 2016 #1
    1. The problem statement, all variables and given/known data
    Warren weights 70 kg and is shot out of a cannon at 25 degrees above the horizontal. the cannon barrel tip is 1.34m above the ground and the cannon has a mass of 203kg.
    What is Warren's initial launch velocity?

    2. Relevant equations
    I don't even know

    3. The attempt at a solution
    I think that this problem is missing some info, or i'm really bad at physics
    Last edited by a moderator: Apr 27, 2016
  2. jcsd
  3. Apr 27, 2016 #2


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    Gold Member

    Doesn't your textbook give you a list of equations for whatever you're learning?
  4. Apr 27, 2016 #3
    We don't go by the textbook, she teaches us with labs and stuff, there are several equations but none of them fit
  5. Apr 27, 2016 #4
    Also this is review for my final and we learned it a while back, i'm taking a practice test and need to get this question right
  6. Apr 27, 2016 #5


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    Gold Member

    Post the equations that you do know.
  7. Apr 27, 2016 #6
    d = vi•t + 0.5*a*t2
    vf = vi + a•t
    vf2 = vi2 + 2*a•d
    that's about it, i can't find a lot of formulas pertaining to initial launch velocity
    Last edited by a moderator: Apr 27, 2016
  8. Apr 27, 2016 #7


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    Homework Helper

    What happens to Warren after he leaves the cannon? Without knowing that, you can't determine what Warren's initial launch velocity was.
  9. Apr 27, 2016 #8


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    What numbers in your problem matches the variables in those equations?
  10. Apr 27, 2016 #9


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    Staff: Mentor

    If that is the complete problem statement, the problem does not make sense.
    Is there something else given? Maybe in a second part, or in a sketch of the problem?
  11. Apr 28, 2016 #10
    Guys, I went to my professor and she said that it was missing the range, sorry for sounding really confusing.
  12. Apr 28, 2016 #11
    And thanks for trying to help me, i did get an A+ on the homework, which is the best possible outcome
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