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Explain speed limits on curved ramp with Newton's Laws

  1. Jul 12, 2017 #1
    1. The problem statement, all variables and given/known data
    Discuss how Newton’s Laws can be used to explain the introduction of transportation
    safety features such as:

    Speed Limits on curved ramps

    2. Relevant equations
    Newton's 2nd Law: F=ma

    3. The attempt at a solution
    I believe that according to Newton's first law objects that are in motion would want to stay in motion. So it would be harder for a car to break on a curved ramp, as it gravitates towards the centre of the curve.

    Im not sure how the second and third law apply to this question though
     
  2. jcsd
  3. Jul 13, 2017 #2

    kuruman

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    Did you mean "brake"?
    Even so, you did not explain why a curved ramp has a speed limit. You may wish to think about what considerations go into setting that speed limit. Why is the speed limit lower when the radius of curvature is smaller? Why is it easier to make the turn when the ramp is tilted inward as opposed to being horizontal? Why is it easier to make a turn when the road is dry as opposed to icy? And so on ...
     
  4. Jul 13, 2017 #3
    I know that there is less friction on an icy road rather than a dry one, as the coefficient of friction is less with rubber on ice as supposed to rubber on concrete or asphalt. Same with it being wet as the coefficient of friction is less, resulting with less friction, and being unable to slow down faster. We haven't really gone into curvature so based on something I read on a forum I assumed the car would gravitate towards the centre of the curve, however, we had not learned this in class. I also know the third law is for every action there is equal and opposite force, however, I don't see how this applies to this situation. I know that the car has a force on the road, and the road is pushing up on the car, but does that have anything to do with the speed?
     
  5. Jul 13, 2017 #4

    SammyS

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    There is quite a bit of extraneous stuff there.

    Let's go back to something you stated in your first post.
    There's a bit more to Newton's first law. What is the full statement of this Law ?
     
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