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Homework Help: 3Dvectors ?

  1. Sep 18, 2005 #1
    3Dvectors !?

    Given; A=<3,-2,-4>m/s^2 , V0=<1,2,3>m/s, R0=<30,-80,40>m, T=8s.
    Find; r0, V, Vave......?

    Is this 3D vector question? What formulas should I use for finding these values?? Please help...
     
  2. jcsd
  3. Sep 18, 2005 #2
  4. Sep 18, 2005 #3
    position...i'm assuming its find r1
     
  5. Sep 18, 2005 #4
    Given; A=<3,-2,-4>m/s^2 , V0=<1,2,3>m/s, R0=<30,-80,40>m, T=8s.

    duh, i should have looked at the units.....maybe i should get some sleep(it is 1:26am here)


    well, i'd go with [tex]\vec{R}=\vec{R_0}+\vec{v_0}t+\frac{1}{2}\vec{a}t^2[/tex] to find r. you can use [tex]\vec{v}=\vec{v_0}+\vec{a}t[/tex] to find v. [tex]\vec{v}_{avg}=\frac{\vec{v}+\vec{v_0}}{2}[/tex] to find out avg velocity.


    edit: yes, it is a 3-d vector question
     
  6. Sep 19, 2005 #5
    So...should I break A, V0, and R0 into their components form (like A=2i-4j-3k) and plug them into the kinematics equations?
     
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