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

Projectile Motions

  1. Mar 28, 2005 #1
    Hi, I'm trying to find out how a function relating [tex] \theta [/tex] and time together. this is because, in many cases of projectile motion, they do give us say, the angle at various spots of a particle's trajectory or velocities so that we solve for theta. Is it possible to create a function so that I know theta straight away just by substituting in the variable time??
     
  2. jcsd
  3. Mar 28, 2005 #2

    dextercioby

    User Avatar
    Science Advisor
    Homework Helper

    What is the angle [itex] \theta [/itex]...?Is it somehow connected to the double-slit experiment...?

    Daniel.
     
  4. Mar 28, 2005 #3
    What do projectiles have to do with the double slit experiment? :confused:
     
  5. Mar 28, 2005 #4

    dextercioby

    User Avatar
    Science Advisor
    Homework Helper

    They do,u see,it's all clear to me:projectiles,double slit experiments and Copenhagen vs.other QM interpretations...If u don't believe me read here and here


    Daniel.
     
  6. Mar 28, 2005 #5

    SpaceTiger

    User Avatar
    Staff Emeritus
    Science Advisor
    Gold Member

    And in case you're not doing the double slit experiment... :wink:

    [tex]v_x=v_{x,0}[/tex]
    [tex]v_y=v_{y,0}-gt[/tex]
    [tex]x=x_0+v_{x,0}t[/tex]
    [tex]y=y_0+v_{y,0}t-\frac{1}{2}gt^2[/tex]

    Now I'm not sure what you mean by [tex]\theta[/tex] either, but it could be:

    [tex]tan(\theta)=\frac{v_y}{v_x}=\frac{v_{y,0}-gt}{v_{x,0}}[/tex]
    [tex]tan(\theta)=\frac{y}{x}=\frac{y_0+v_{y,0}t-\frac{1}{2}gt^2}{x_0+v_{x,0}t}[/tex]

    If not, please clarify what you mean by [tex]\theta[/tex].
     
  7. Mar 28, 2005 #6

    dextercioby

    User Avatar
    Science Advisor
    Homework Helper

    Aren't "x" and "y" perpendicular,so the angle between them [itex] \frac{\pi}{2} [/tex] and the tangent of this angle is [itex] \infty [/itex]...?The same goes for velocity vector's projections onto the rectangular Oxy...:bugeye:

    Daniel.
     
  8. Mar 28, 2005 #7

    SpaceTiger

    User Avatar
    Staff Emeritus
    Science Advisor
    Gold Member

    Uh, what? This isn't the angle between x and y. "x" and "y" represent the sides of a right triangle with one vertex at the origin. The angle is relative to the horizontal.
     
  9. Mar 28, 2005 #8

    dextercioby

    User Avatar
    Science Advisor
    Homework Helper

    You're right.I think among your 2 options lies the OP's answer to his question,unless it's something which would defy logics.

    Daniel.
     
  10. Mar 29, 2005 #9
    hey, that helped, thanks alot.

    I was not looking for the double-slit exp. though lol. I wouldn't have posted that in the classical physics forum. and that helped too, btw.

    : )
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?



Similar Discussions: Projectile Motions
  1. Projectile Motion (Replies: 3)

  2. Projectile Motion. (Replies: 2)

  3. Projectile motion (Replies: 2)

Loading...