1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
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: Projectile motion with two angles

  1. Oct 16, 2011 #1
    First, I struggled with whether to put this in advanced or intro physics. I read the sticky, and since this is a 300 level class that is taken at the junior level in the physics BS program at my school, I put it here. If it's considered too simplistic for advanced physics, I apologize.

    I've attempted a solution and come up with something painfully close to the desired result, and I have no idea where I'm going wrong. I would really appreciate some insight.

    1. The problem statement, all variables and given/known data

    3. The attempt at a solution
  2. jcsd
  3. Oct 17, 2011 #2

    Filip Larsen

    User Avatar
    Gold Member

    Your answer fits if you define "elevation" as being measured from horizontal and not from the slope as you have done it.
  4. Oct 17, 2011 #3
    Oh gods! How stupid of me! My angle should be [itex]\alpha[/itex] - [itex]\phi[/itex], not just [itex]\alpha[/itex]. That makes my derived answer sin([itex]\alpha[/itex]-[itex]\phi[/itex])*cos([itex]\alpha[/itex]-[itex]\phi[/itex]+[itex]\phi[/itex]) = cos([itex]\alpha[/itex])*sin([itex]\alpha[/itex]-[itex]\phi[/itex]) which is, of course, the desired result. I should sleep more. Thanks for the reply!
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook