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Homework Help: Can i just multiply these?

  1. Oct 31, 2006 #1
    can I just multiply 3.47 m/s/s by 5 seconds to get my speed after that amount of time? for example:

    . A European sports car dealer claims that his car will accelerate
    at a constant rate from rest
    to a speed of 100 km/hr (28 m/s) in 8.00 s. What is the speed
    after the first 5.00 s of

    a.44.4 m/s b. 34.7 m/s c. 28.7 m/s d. 17.4 m/s e. 8.7

    First I find the acceleration to be 3.47 m/s^2 now can i just times by 5? If so i get 17.4 m/s Is this correct?
  2. jcsd
  3. Oct 31, 2006 #2
    yes that is correct

    if u are in doubt you can always look at what you're given and your kinematic equations to get your answer
  4. Nov 1, 2006 #3
    You are right in this context but make sure you have an accurate bearing of your question. It would not have been correct if the car did not start from rest.
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