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    (Original post by KINGYusuf)
    Thank you very much, sorry I'm just really bad at Vectors lol
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    Can anyone explain how to draw a triangle of forces for this? The strings are light and inextensible, the line AB ks horizontal

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    (Original post by KINGYusuf)
    Can anyone explain how to draw a triangle of forces for this? The strings are light and inextensible, the line AB ks horizontal

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    tensions up the strings and weight vertically down
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    Is it alright to write unit vectors as i or j with a circumflex/hat, like î?
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    if a rod is at the point of tipping about a support, do the reactions of the supports equal to 0?
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    (Original post by Kamara7)
    Is it alright to write unit vectors as i or j with a circumflex/hat, like î?
    that should be fine, i do it like that usually.
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    (Original post by amelienine)
    if a rod is at the point of tipping about a support, do the reactions of the supports equal to 0?
    When it says it tilting about a point where the support is - the other support will have a reaction equal to zero.
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    (Original post by amelienine)
    that should be fine, i do it like that usually.
    Thanks!
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    (Original post by Marxist)
    When it says it tilting about a point where the support is - the other support will have a reaction equal to zero.
    Alright thank you!
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    (Original post by amelienine)
    that should be fine, i do it like that usually.
    Try question June 2013 Q6 - good example of this.
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    I've used June 2013 after 14-15 - seemed to have lost about 4 marks from a silly error. Slump.
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    (Original post by amelienine)
    if a rod is at the point of tipping about a support, do the reactions of the supports equal to 0?
    If a beam is on two supports A and B, and the beam is on the point of tilting about B, then the magnitude of the reaction of the support at A will be 0N. If you then decide to take moments about the support B, then you can ignore this reaction force also This is useful if you're trying to work out the mass of a weight at some point on the beam for example, since you don't have to worry about either support's reaction force!
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    (Original post by Marxist)
    I've used June 2013 after 14-15 - seemed to have lost about 4 marks from a silly error. Slump.
    Dang nice one! June 13 was a bad year for maths past papers xD Hoping they don't pull that again this year...
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    (Original post by Don Pedro K.)
    Dang nice one! June 13 was a bad year for maths past papers xD Hoping they don't pull that again this year...
    Nah, what annoyed me was a silly error otherwise I wouldn't mind.
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    I am freaking out... I can't do this
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    In a pulley is the component of weight always opposite to motion?
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    (Original post by ryandaniels2015)
    In a pulley is the component of weight always opposite to motion?
    not necessarily, one end of the pulley goes down when the other end goes up
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    (Original post by candol)
    not necessarily, one end of the pulley goes down when the other end goes up
    Sorry i meant the one on the plane?
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    (Original post by ryandaniels2015)
    Sorry i meant the one on the plane?
    hi, not necessarily in that case either. Often the question will tell you explicitly which way movement is occurring or will give you a big clue.
    Clearly if the plane is horizontal the weight over the edge will move down.
    The slope question could see movement either way.
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    Ok thanks, but if travelling up the plane, the component of weight will be down?
    (Original post by candol)
    hi, not necessarily in that case either. Often the question will tell you explicitly which way movement is occurring or will give you a big clue.
    Clearly if the plane is horizontal the weight over the edge will move down.
    The slope question could see movement either way.
 
 
 
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