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    So for part (a) was to find the tension in the string, which I found was 33.6N, for part (b) do I resolve downwards: mg-T=ma?
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    Make an equation to find the tension in m like you did with 4. Since you already have the value of T you can substitute that in to find m.
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    I didn't read your post properly but I've realised that you've got the equation wrong too. The tension is going in the same direction as the acceleration on m so the tension should be positive. Always draw the directions of acceleration with a double headed arrow so you don't make that mistake.
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    (Original post by AspiringUnderdog)
    I didn't read your post properly but I've realised that you've got the equation wrong too. The tension is going in the same direction as the acceleration on m so the tension should be positive. Always draw the directions of acceleration with a double headed arrow so you don't make that mistake.
    Okay so
    mg+T=ma
    m = T/(g+a)
    m = 3kg right ?
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    T is in a different direction to mg so it would be T - mg.
    When you use F = ma in this case you are resolving a force to find F which in this case is the vertical force.
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    (Original post by AspiringUnderdog)
    T is in a different direction to mg so it would be T - mg.
    When you use F = ma in this case you are resolving a force to find F which in this case is the vertical force.
    Okay thanks
 
 
 
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