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Homework Help: 2 Problems i need hlep with, Acceleation and Time

  1. May 17, 2009 #1
    1. ok so i have my physics packet and i need help bad. the problem is...
    How long does it take a car to cross a 45m wide intersction after the light turns green if it accelerates from rest to constant 14.3 m/sec^2
    Find T


    A Car accelerates along a straight road from rest to 495 km/h in 16 sec. what is the magnitude of its average acceleration
    Find a= ? km per hour/ sec
    Find a= ? m/s^2

    2.i don't have much equations for this problem in any of my notes
  2. jcsd
  3. May 17, 2009 #2
    Do you the two velocity and position kinematic equations?



    Xf=final position
    Xi=initial position
    Vf=final velocity
    Vi=initial velocity
  4. May 17, 2009 #3
    i do have the 2nd one but i dont see how they can help me
  5. May 17, 2009 #4
    Try and use the first equation for your first problem.
    You dont need more then that
    Last edited: May 17, 2009
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