Recent content by jambraun

  1. J

    Trajectory - different start and end height, limited knowns

    lol, you're absolutely right. Here's the conversion using degrees. I'll have to play with it so the projectile stays on the playfield / looks believable:
  2. J

    Trajectory - different start and end height, limited knowns

    I think that may have done it! Thanks for the help. I'll drop this into my program and see if it hits the target :)
  3. J

    Trajectory - different start and end height, limited knowns

    Sorry! I changed my values after you mentioned I could alter some variables to have the time change...that was probably a bad idea since it changes the help I'm asking for. Between you and Cwatters I'll write up my final equations and repost with the completed version. I think the answer is...
  4. J

    Trajectory - different start and end height, limited knowns

    I thought I did :/ the answer to the above came out to be -(40/106) which is still waaaay off the mark. I'm posting from my phone so I can't do anything elaborate for a bit
  5. J

    Trajectory - different start and end height, limited knowns

    I'm failing in the substitution and rearrange steps. It's always been my weakness. Can I beg you to show me what the correct equation for g is?
  6. J

    Trajectory - different start and end height, limited knowns

    ok, I need someone to check my math... here's what happens when I plug in the variables: The hardest equation by far is to find gravity (which must be incorrect). Alternatively, if I solve for gravity by hand... 40 = (175/(2*cos(70)))*2*sin(70)-.5*g*2^2 40 = 212.52-2g... Help me out where...
  7. J

    Trajectory - different start and end height, limited knowns

    Oh, I got lost when you said I could change the gravity to get the needed rise. I didn't understand if I'm solving for gravity or just choosing a greater gravity? Also, for solving the difference in Y, are you saying: But I don't have to use steps 1 and 2 from notes, just plug in the...
  8. J

    Trajectory - different start and end height, limited knowns

    Sorry, the equation variables aren't something I can guess at while running for the program to work. Plus, doesn't calculating the initial velocity from the original equation of X always land short of the mark? I believe that's why it's a 3 step process, obtaining the true time in the air from...
  9. J

    Trajectory - different start and end height, limited knowns

    6.26s is too long (unfortunately). Can I fudge gravity or angle to decrease the time? I still need to figure out how to displace the distance so the target is struck at the right height. We'll still have to talk about how to account for displacement I think. Here's what I was trying to use...
  10. J

    Trajectory - different start and end height, limited knowns

    I knew something was up...I can be flexible on time or gravity. let me post the equations I've been working with in the morning but I still think my hangup is with the height displacement. Thanks!
  11. J

    Trajectory - different start and end height, limited knowns

    Thanks CWatters, my major notes are in my notebook at home; I'll post them in the morning. I think my primary issue is displacement of X to compensate for the differing heights. I have no problem calculating the launch and land from the same altitude which is pretty straight forward.
  12. J

    Trajectory - different start and end height, limited knowns

    Homework Statement A projectile is fired from a cannon at X-distance of 25m (X=25), height 10m (y=10), and fixed angle (53-degrees). After 3 seconds, the projectile hits its mark at different height 50m (y=50), and at a range of 175m (X=200). Gravity is normal and there is no wind resistance...
Back
Top