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    Hi guys,
    I hae a question which I am struggling on.

    A particle of mass m moves under the action of a resistance of magnitude mkv^2 and a restoring force of magnitude mAk towards the origin x = 0

    Write down the equation of motion in the cases

    a) x > 0 and v > 0
    b) x > 0 and v < 0
    c) x < 0 and v < 0

    Can anyone please help me here?
    Thanks
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    You need to work out what the forces are and what direction they act in.

    Hint:

    A resistive force acts in the opposite direction to the velocity.

    A restorative force acts in the opposite direction the the displacement (from the origin).
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    for a) I have d^2x/dt^2 = Ak - kv^2
    for b) i have d^2x/dt^2 = Ak + kv^2

    I am not sure about c)
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    Which direction does the 'Ak' force go in?
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    (Original post by DFranklin)
    Which direction does the 'Ak' force go in?
    The information above is all that is given to me.

    I know I am right for a) and b) but I cannot get c). Is there anyone out there who can help?
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    (Original post by DFranklin)
    Which direction does the 'Ak' force go in?
    It says towards the origin x = 0
 
 
 

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