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Homework Help: Minimum deaceleration untll the car stops

  1. Sep 12, 2006 #1
    what am i doing wrong??
    every time i try to answer this i get t=.2s and a=-1651ms^-2

    the problem reads....
    A car traveling at 25mi/h is to stop on a 35m-long shoulder of the road. (a) What is the required magnitude of he minimum acceleration? (b)How much time will elapse during this minimum deaceleration untll the car stops.

    i used the equation....

  2. jcsd
  3. Sep 12, 2006 #2
    i think the first time is to convert 25mi/h into meters per second.

  4. Sep 13, 2006 #3
    Yes, use 1 mile =1.6km, and don't forget to convert to m/s, so you need to change out of km/h. 1h=3600s. That equation is right.
  5. Sep 17, 2006 #4
    yes i did convert to m/s wrong thanks for the help.:rofl: :tongue2:
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