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Homework Help: HELP! car brakes to stop before cliff how do you find work

  1. Mar 11, 2009 #1
    A car and driver weighing 5710 N passes a sign station (bridge out in 23.1 m) She slams on her brakes and the car decelerates at a constant rate of 9.94 m/s^2. Accel of grav is 9.8 m/s^2. What is the ganitude of work done, stopping the car before it falls.

    We dont know how to do it at all =/ help please!
  2. jcsd
  3. Mar 11, 2009 #2
    HELP! its due at 11 TONIGHT =)
  4. Mar 11, 2009 #3
    I'm not sure how to answer your question, but if you read the forum rules, you need an attempt of some sort before you get any help. Most certainly, they will not do the question for you.

    Looks like you're out of luck.
  5. Mar 11, 2009 #4
    you have to know the friction of the road as well as the initial velocity in order to find out, then you would use the work-kinetic energy theorem.
  6. Mar 12, 2009 #5
    You would also need to know the initial velocity and or the time that it takes for the car to stop, also, you were also talking in two components, and work is a scalar, and you didn't specify in what component. So yeah…

    Sorry, cannot help you there.
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