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Homework Help: Help instaneous velocity

  1. Sep 21, 2013 #1
    The position of a particle moving in a straight line during a 10–second trip is s(t) = 3t2 − 3t + 5 cm.Find a time t at which the instantaneous velocity is equal to the average velocity for the entire trip.
  2. jcsd
  3. Sep 21, 2013 #2
    Average velocity = (x2 - x1)/Δt

    How do you find instantaneous velocity?
  4. Sep 21, 2013 #3
    the derivative
  5. Sep 21, 2013 #4
    what does x represent?
  6. Sep 21, 2013 #5
    The position. x2 - x1 is the change in position. Your object starts at one point, and ten seconds later, it's somewhere else. That somewhere else is x2.
  7. Sep 21, 2013 #6


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    Your "s". The average speed, between t= 0 and t=10, is (s(10)- s(0))/(10 - 0). Calculate that, set it equal to s'(t) and solve for t.
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