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Homework Help: Mechanics displacement Question

  1. Jul 24, 2010 #1
    1. The problem statement, all variables and given/known data
    At time t = 0 a drag racer starts from rest at the origin and moves along a straight line with velocity given by v = 5t^2, where v is in m/s and t in s. The expression for the displacement of the car from t = 0 to time t is
    (a) 5t^3
    (b) 5t^3/3
    (c) 10t
    (d) 15t^2
    (e) 5t/2


    2. Relevant equations
    (Vfinal-Vinitial/2)t=X
    Vfinal=5t^2

    3. The attempt at a solution

    The manual says B

    But I keep Getting 5t^3/2

    Vfinal=5t^2

    Vinitial=0
    so
    (5t^2/2)t=x
    5t^3/2
     
  2. jcsd
  3. Jul 24, 2010 #2
    u have to apply integration here
     
  4. Jul 24, 2010 #3
    Oh... Im not versed in calculus at all :l. could you explain the process?
     
  5. Jul 24, 2010 #4
    express v as ds/dt. then bring the dt to other side of the equation. then integrate both sides.
     
  6. Jul 24, 2010 #5
    Alright, thanks for your help!
     
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