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Determining the value of a constant

  1. Oct 20, 2015 #1
    Example 3 shows the derivation of one of the kinematics equations. I am quite familiar with it. At the part where it says dx/dt = gt + constant, how does one determine if constant = x_0 or v_0? Thank you.
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  3. Oct 20, 2015 #2

    Simon Bridge

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    You use the physical description of the situation ... in this case, just checking the units are consistent should work.
     
  4. Oct 20, 2015 #3
    That makes sense. Thanks!
     
  5. Oct 20, 2015 #4

    Simon Bridge

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    Since the constant term does not depend on time - you can always find the expression for it by putting ##t=0## into the equation.
    In your example ##v=gt+c## you get ##v(0)=c## ... because you understand from the physics, that the time derivative of displacement is velocity.
     
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