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: Can't figure this out

  1. Sep 1, 2004 #1

    SMS

    User Avatar

    A particle moves in the x-y plane with constant acceleration. At time t = 0 s, the position vector for the particle is d = 2.2 m x + 8.2 m y. The acceleration is given by the vector a = 4.5 m/s2 x + 2.2 m/s2 y. The velocity vector at time t = 0 s is v = 3.3 m/s x - 4.3 m/s y. Find the magnitude of the velocity vector at time t = 8.3 s.

    I never liked vectors :mad:
     
  2. jcsd
  3. Sep 1, 2004 #2

    Galileo

    User Avatar
    Science Advisor
    Homework Helper

    No man. Change that attitude. Vectors are like, totally awesome :cool:
    You'll appreciate them when you take linear algebra.

    Anyway, simply view this problem as two one-dimensional problems.
    The x- and y coordinates are independent.
    Since the acceleration is constant, the formula for the speed as a function of time is:
    [tex]v_x(t)=v_{x0}+a_xt[/tex]
    And a similar equation for [itex]v_y(t)[/itex].

    You can calculate
    [tex]v(t)=\sqrt{v_x(t)^2+v_y^2(t)}[/tex]
    with this.
     
  4. Sep 1, 2004 #3

    arildno

    User Avatar
    Science Advisor
    Homework Helper
    Gold Member
    Dearly Missed

    No, they start rocking when taking physics :wink:
     
  5. Sep 1, 2004 #4

    SMS

    User Avatar

    U guys are right

    Vectors don"t suck. I think I was just frustrated with the rest of my work.

    I am taking physics and that was a physics problem.

    Any ways I got all the answers right on CAPA, so everything rocks!!! :tongue:

    Time to :zzz: :zzz:
     
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook