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Need a quick answer please!

  1. Apr 14, 2009 #1
    If a brake caliper exerts 1000kg on a brake pad what is the force due to the this weight?

    It can't be umg because there is no g in horizontal weight.

    Does g = 1

    Therefore F = m
     
  2. jcsd
  3. Apr 14, 2009 #2

    Hootenanny

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    Your question does not make sense. A brake caliper cannot 'exert' 1000 kg on anything, since kilograms is a measure of mass and not force.
     
  4. Apr 14, 2009 #3
    I have a specification for a brake caliper that states its clamping force is equal to 4136kg. I know force doesn't equal 4136 but what does clamping force mean then
     
  5. Apr 14, 2009 #4

    Hootenanny

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    Could you attach or link to the specification document?
     
  6. Apr 14, 2009 #5

    alxm

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    I'd interpret it at the equivalent of 4136 kg, that is 4136 kilogram-force or kiloponds. So the force would be 4136/g or about 422 Newtons.
     
  7. Apr 14, 2009 #6
    http://www.dcsint.nl/pdf/5020a.pdf [Broken]

    Thank you for your fast respones
     
    Last edited by a moderator: May 4, 2017
  8. Apr 14, 2009 #7

    Hootenanny

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    In which case, I'd agree with alxm's interpretation,
    Bloody engineers :tongue2:
     
    Last edited by a moderator: May 4, 2017
  9. Apr 14, 2009 #8
    does this mean the static frictional force is independent of vehicle mass?
     
  10. Apr 14, 2009 #9

    russ_watters

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    The force between the brake pads and rotors is not a function of gravity. It is generated hydraulically. If that's the static friction you are talking about, then you are correct, it is not a function of vehicle mass. Judging by the question you asked yesterday, however, I'm guessing you now asking about tires and are still confused about this...
     
  11. Apr 14, 2009 #10

    russ_watters

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  12. Apr 14, 2009 #11
    That can't be true. I have a car stopping with kinetic friction as u*m*g = 0.7 * 1000 * 9.8 = 6860N

    I thought static (ABS) is more effective than kinetic

    Static coefficient * force = 0.5 * 422 = 211N

    This can't be right
     
  13. Apr 14, 2009 #12
    oh, cheers
     
  14. Apr 14, 2009 #13
    can anybody give me an example of average clamping forces for vehicles
     
    Last edited: Apr 14, 2009
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