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    how do you find the COF without mass?
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    (Original post by Snowy_TM)
    how do you find the COF without mass?
    Example?
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    10km/h
    130m stopping distance
    -25m/s deceleration
    can you help me with the formula and explain how to do it for me please ?
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    (Original post by Snowy_TM)
    10km/h
    130m stopping distance
    -25m/s deceleration
    can you help me with the formula and explain how to do it for me please ?
    F = frictional force
    N = normal force

    F = μN
    normal force is the weight
    F=μmg [1]

    for a force accelerating a mass
    F=ma [2]

    combine [1] & [2]

    ma=μmg

    m cancels

    a=μg

    ---
    PS your numbers look iffy, check how you got a deceleration of 25m/s^2
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    A=-u^2/2s
    = 10^2/2*130
    =0.384m/s
    Can you put my results into an equation please to find the cof?
 
 
 
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