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Does anyone know how to solve i try to self learn?

  1. Jun 3, 2012 #1
    The equations used are:
    2)fk = μkN
    3)fs ≤ μsN
    4)Fs = - kx

    Here are the questions:
    1. If ΣF is 10N and a=1 m/s^2, find m using the first equation
    2. Given ΣF = fk, m=250 kg, μk=0.2, and N = 10m, find a.
    3. ΣF=T-10m, but a=0 m/s^2. Use the first equation to find m in terms of T.
    4. Given the following values, determine if the third equation is valid. ΣF =fs, m=90kg, and a=2 m/s^2. Also, μs=0.1 and N=5N.
    5. Use the 4th equation to solve for F, if k=900 N/m and x=0.15m
    6. Use this equation ( vf=v0+at) and (ΣF=ma) find ΣF when m=12kg, vo= 15m/s,vf=5/ms and x=0.15m
  2. jcsd
  3. Jun 3, 2012 #2
    Well let's start with the first problem,

    You know:
    ΣF = 10N
    a = 1 m/s^2
    m = ?

    And better yet, you know you have to use ΣF = m*a

    Are you familiar with how to solve for a variable in an algebraic equation?

    For example, can you solve for x in this equation?

    6x = 52
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