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Homework Help: Force questions

  1. Feb 5, 2008 #1

    can someone help me please with these questions?
    i have read all the newton law but still not understanding these question properly

    1.what is an force?
    2.how do we know a force is acting?
    3.what effect can force have?
  2. jcsd
  3. Feb 5, 2008 #2
    1) A force is that entity that tends to cause a body of mass to accelerate.
    2) This is tricky. I think they mean "how do we know when a net force is acting", and the answer would be:"we observe an acceleration of the body to which the force is applied"
    3) Acceleration; deforming a body.
  4. Feb 5, 2008 #3
    in definition F=ma from newtons law- m in kg and a in m/s so you end up with a kg*m/s, which is called a newton. An example...

    You have a 300g ball on a string, what is the force of gravity on the ball?


    acceleration due to gravity is 9.8m/s[tex]^{}2[/tex] so...

  5. Feb 5, 2008 #4
    a is m/s[tex]^{2}[/tex] so you actually end up with [tex]\frac{kg * m}{s^{2}}[/tex] which really is called a newton, denoted as N.
  6. Feb 5, 2008 #5
    Well, can change mass and can change velocity...i guess that's it...
  7. Feb 5, 2008 #6


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    A force is what causes a mass to accelerate.

    A force acts when a body is "accelerating" so to say
    A force can cause a mass to accelerate,change velocity(and speed)
  8. Feb 6, 2008 #7
    thank you guys this was great help from your comments
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