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    I need some help.

    "A particle of mass m kg slides down a smooth inclined plane with an acceleration of 2 ms^-2. Find the inclination of the plane to the horizontal."

    I know that I can use F=ma to calculate the mass, and then subsitute it into mgSin theta, But I don't know how to get the mass?
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    mg sin theta = the component of gravity acting in the direction of motion

    You're also right with your introduction of Newton's 2nd Law.

    Now equate these 2 and substitute in anything you know and cancel anything you can.
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    Thanks for the help.
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    However... I am now stuck on this question about vectors:

    "A particle of mass 500 grams starts from rest at the point A which has position (4i + 2j)m. The resultant force on the particle is (i + 2j)N. Find the position vector of the particle after 3 seconds. "

    How do I use F=ma for vectors?
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    In exactly the same way as usual. (you might wanna convert mass to standard units first)

    F/m = a

    you have a, t, u and you want s

    Remember s will have to be worked out using the initial position vector
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    (Original post by Student403)
    In exactly the same way as usual. (you might wanna convert mass to standard units first)

    F/m = a

    you have a, t, u and you want s

    Remember s will have to be worked out using the initial position vector
    Do I treat i and j components separately still?
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    (Original post by Electrogeek)
    Do I treat i and j components separately still?
    Yeah keep em separate since you want to work out the position vector. Remember to multiply/divide both i and j components whenever you manipulate expressions
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    (Original post by Student403)
    Yeah keep em separate since you want to work out the position vector. Remember to multiply/divide both i and j components whenever you manipulate expressions
    Cool. Thanks for the help.
 
 
 
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