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Homework Help: Question about notation in physics

  1. Jan 26, 2012 #1
    So it says that a particle is going with a velocity of 5i m/s at t = 0 and varying acceleration a = 6√t j.
    it asked me to find the velocity and position of the particle as a function of time.
    So i did an integral of the acceleration to get velocity and did the integral of the velocity to get the position. I was wondering whenever i write the equation as a function of time, do i still need that arrow (→ ) on top of the v for vector and r for position?
     
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  3. Jan 26, 2012 #2

    SammyS

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    If it's a vector, then yes, we usually put the arrow above the variable.

    [itex]\vec{r}(t) = x(t)\hat{i}+t(t)\hat{j}+z(t)\hat{k}[/itex]
     
  4. Jan 26, 2012 #3
    so if I solved the integral and I got like
    r(t) = 8t^2 + 5t
    I put the arrow on top of the arrow since it's a vector. I get that ...
    But do I still include the i and j?
    so would it be r(t) = 8t^2 i + 5t j ?
     
  5. Jan 26, 2012 #4

    SammyS

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    Yes, use the [itex]\hat{i}[/itex] & [itex]\hat{j}\,.[/itex]

    If the left side of an equation is a vector, then the right side must also be a vector.
     
  6. Jan 26, 2012 #5
    Thank you! :)
     
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