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Homework Help: Help with velocity problem

  1. Apr 25, 2005 #1
    The position of an object moving along x-axis is given by x=a+b(t*t) where a =8.5m, b=2.5m/(s*s) and t is time. What is the velocity at t=2s? I think differential calculus should be used :confused:
     
  2. jcsd
  3. Apr 25, 2005 #2
    If that x equation is x = a+bt^2, then just differentiate wrt to time to get velocity.
     
  4. Apr 25, 2005 #3
    Yupp, just get dx/dt and then make t = 2.
     
  5. Apr 26, 2005 #4
    Is it this:
    dx/dt = d(a+bt^2)/dt
    After this what should I do?
     
  6. Apr 26, 2005 #5

    James R

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    Do you know how to differentiate?

    If [itex]y = a + bx^2[/itex], what is dy/dx?

    You have [itex]x = a + bt^2[/itex], and you know v=dx/dt, so what is v(t)?
     
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