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    (Original post by .Username.)
    Can anyone tell me the all of the assumptions I.e. what rod, plank, particle, lamina mean (and any others)
    For a uniform frame the mass is proportional to its length.
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    (Original post by StUdEnTIGCSE)
    Well you could determine them like this:
    Keep you index finger at the point around which you are taking moments, then without moving it swing you thumb over and in the direction of the arrow of the force. After you have passed the arrow head see how best it can make a circle around that point. That circle will show if it is clockwise or anticlockwise.

    You can use either the thumb or the index finger for either. What's seems more comfortable...
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    Take that for just an example, could you tell me what's clockwise and anticlockwise say about B?
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    (Original post by JenniS)
    have you done a triangle thing for A to work out the vertical distance it moved? then just compare GPE
    I don't think I got that?
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    (Original post by Exams v__v)
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    Take that for just an example, could you tell me what's clockwise and anticlockwise say about B?
    Clockwise would be F and R. W is anticlockwise
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    (Original post by Exams v__v)
    Oops, my bad. :P

    Could you help in the basic idea of toppling? What do we need to know?
    Do you have the orange and purple book?
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    (Original post by Exams v__v)
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    Take that for just an example, could you tell me what's clockwise and anticlockwise say about B?
    (Original post by Boy_wonder_95)
    Clockwise would be F and R. W is anticlockwise
    No, F would not create any moment about B as it acts through the point. Just R and W would create a moment.
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    (Original post by Boy_wonder_95)
    Clockwise would be F and R. W is anticlockwise
    How do you do F? W and R are okay
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    (Original post by Anonymous1717)
    Do you have the orange and purple book?
    Yes! What page?
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    Can anyone help me with how you do question 5 january 2006, finding the centre of mass of a a triangle WITHOUT THE LAMINA
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    (Original post by LShirley95)
    No, F would not create any moment about B as it acts through the point. Just R and W would create a moment.
    Yh fair enough.
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    (Original post by Exams v__v)
    How do you do F? W and R are okay
    I wasn't thinking
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    (Original post by LShirley95)
    No, F would not create any moment about B as it acts through the point. Just R and W would create a moment.
    Are you sure? ;o can't we resolve F or something?
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    (Original post by Exams v__v)
    Are you sure? ;o can't we resolve F or something?
    I am sure! A moment is given by F*d; where d is the shortest distance from the line that the force acts through, to the point we're taking moments about. As F acts directly through the point there is no moment as d = 0.

    You could think about it in a number of ways: it is acting neither clockwise nor anticlockwise around B so how could a moment be created?!
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    (Original post by LShirley95)
    I am sure! A moment is given by F*d; where d is the shortest distance from the line that the force acts through, to the point we're taking moments about. As F acts directly through the point there is no moment as d = 0.

    You could think about it in a number of ways: it is acting neither clockwise nor anticlockwise around B so how could a moment be created?!
    Oh right! That makes sense, haha. Okay how about this. The horizontal at X, is it clockwise or anticlockwise? Taking moment about B. Name:  image.jpg
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    (Original post by JenniS)
    Can anyone help me with how you do question 5 january 2006, finding the centre of mass of a a triangle WITHOUT THE LAMINA
    So thats part (a) right? How stuck are you? Do you know where to begin?
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    (Original post by Exams v__v)
    Yes! What page?
    56

    Even if you've figured out that angle question, can you tell me where it's from so I can see if I can do it?
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    (Original post by Anonymous1717)
    56

    Even if you've figured out that angle question, can you tell me where it's from so I can see if I can do it?
    Where it's from, you mean?
    And thanks!
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    Have to say I'm pretty worried about M2 tomorrow. Why are the grade boundaries always so absurdly high?! Not exactly the easiest unit but 71 for 90 UMS on quite a few past papers? So easy to lose a large chunk of marks from 1 mistake in mechanics as well :mad:
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    (Original post by MasterYi)
    So thats part (a) right? How stuck are you? Do you know where to begin?
    after panicking I realised what to do its that sum of mass thing
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    Can someone okease tell me. The horizontal force at X, is it clockwise or anticlockwise? Taking moment about B. Name:  image.jpg
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