Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Homework Help: Finding an angle of a projectile for a specific distance

  1. Jan 18, 2010 #1
    1. The problem statement, all variables and given/known data

    A fire hose held near the ground shoots water at a speed of 6.5 m/s. At what angle(s) should the nozzle point in order that the water land 2.0m away. Why are there two different angles?

    2. Relevant equations

    v=v0 +at v^2=v0^2 +2ad d=V0t+1/2at^2

    3. The attempt at a solution

    I'm not sure how to go about solving this. I've gotten as far as this (calling the angle x)

    Vy = Vosinx and Vx = Vocosx

    Any help would be much appreciated, I don't understand where to go from here. It seems like none of the equations are going to go anywhere.

    Thank you very much for your time...
  2. jcsd
  3. Jan 18, 2010 #2


    User Avatar
    Science Advisor
    Homework Helper

    Welcome to PF!

    Hi trexmatt ! Welcome to PF! :smile:

    (have a theta: θ and try using the X2 tag just above the Reply box :wink:)
    Yes, those are the equations to use :smile:

    (except don't use x for two different things!! :rolleyes:)

    Now treat the x and y directions separately (a = -g for y, a = 0 for x), to get a pair of equations involving θ, from which you can then eliminate t.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook