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Homework Help: Big Problem

  1. Apr 7, 2004 #1
    ok I have another problem here. Please help me. Thank you in advance.

    A 1.50 kg sled scrapes down a grassy incline where the coefficient of friction is 0.678. The sled moves at a constant speed f 4.50 m/s and it takes 12.5 seconds to travel the entire length of the hill to the bottom.

    After the sled passes, a 5.00kg rolling cart (with an effective coefficient of friction of .456) goes down the same hill. At the bottom. the cart crashes into a very massive bale of hay (which does not move so this is not a collision problem). The ha bale exerts an average force of 98.0N on the cart. Calculate how far into the hay bale the cart goes before stopping.

    [Hints: find angle of incline; length of incline; acceleration of cart; speed at bottom of incline]

    I recieved for the angle: 34 degrees
    the length of the incline: 2.78m
    acceleration of cart: 1.78m/s squared
    speed at bottom: 3.15 m/s

    Please inform me if I am wrong on any of those, and please help me to calculate the distance the cart travels in the hay before it stops.
  2. jcsd
  3. Apr 7, 2004 #2

    Chi Meson

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    Delta Mu:

    This is a take-home EXAM. Help from others was specifically forbidden. THis includes people you do not know.

    Hello, I am your teacher.
    Last edited: Apr 7, 2004
  4. Apr 7, 2004 #3
    Hah! This is funny. Good thing you didn't use your real name... :wink:

    Well, not knowing if you really are his teacher (afer all, what are the odds?) I will just say that:
    [tex]F_{ext}x = \Delta E_m = \Delta E_k[/tex]
  5. Apr 7, 2004 #4

    Chi Meson

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    The odds are good. I tell all my students about this forum and encourage them to seek help with homework. HTis is a question from a test, however, and I would request that no one answer it further.
  6. Apr 7, 2004 #5
    Fair enough. I do appreciate the trust you have in your students, and what I posted can be found in every textbook anyway. :smile:
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