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Homework Help: Acceleration is like what?

  1. Sep 25, 2011 #1
    1. The problem statement, all variables and given/known data
    A skier begins skiing straight down a hill having a constant slope starting from rest. if friction is negligible as the skier goes down the hill his
    Acceleration increases with time
    Acceleration is constant with a value less than 10m/s^2
    Acceleration is zero

    2. Relevant equations
    dont need one

    3. The attempt at a solution
    at first i thought the acc. was constant but had a value of about 10m/s^2 (gravity)
    that was wrong.
  2. jcsd
  3. Sep 25, 2011 #2

    Doc Al

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    Staff: Mentor

    That's the acceleration during free fall, not while sliding down an incline.

    Do you think the acceleration down a hill is more or less than that? Hint: Imagine a very long, gentle slope.
  4. Sep 25, 2011 #3
    i would guess it would be more than that.
  5. Sep 25, 2011 #4
    is that right??/
  6. Sep 25, 2011 #5
    What would be more than what? If you can be a little more specific, it would be helpful. And if you give us your thought process we can agree or help with where you might be making a mistake.
  7. Sep 25, 2011 #6
    okay so i guess that acceleration will increase with time. i guess im thinking about it like if you put a skateboard on a hill it gets faster as it rolls down. so would the answer be acceleration increases with time. does this help you?
  8. Sep 25, 2011 #7

    I like Serena

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    Homework Helper

    Nice analogy with the skateboard! :smile:

    But you're mixing up acceleration and speed.
    The speed of the skateboard increases as it rolls down.
    Just like your speed would increase while falling down.

    However, when you fall down, you fall down with a constant acceleration of g = 9.8 m/s2.
    Since you're on a slope now with your skateboard, would your acceleration be more or less than when you fall down?
  9. Sep 25, 2011 #8
    umm less than when you fall down
  10. Sep 25, 2011 #9

    I like Serena

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    Yep! :approve:

    So what's the answer?
  11. Sep 25, 2011 #10
    the answer would be acceleration is constant with a value less than 10m/s2
  12. Sep 25, 2011 #11
    Yes. Good job. :smile:
  13. Sep 25, 2011 #12

    I like Serena

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    Homework Helper

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