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    Please could someone explain why it is the tension of the lower string you make zero instead of the upper string in order to find the maximum time period?

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    (Original post by PhyM23)
    Please could someone explain why it is the tension of the lower string you make zero instead of the upper string in order to find the maximum time period?

    Thanks
    Because otherwise you would have levitating balls
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    (Original post by Gome44)
    Because otherwise you would have levitating balls
    But is it not possible for the bottom string to stay taut without the top string so long as enough force is provided to keep the particle in the air? Or am I just being stupid?
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    aymanzayedmannan
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    (Original post by PhyM23)
    Please could someone explain why it is the tension of the lower string you make zero instead of the upper string in order to find the maximum time period?

    Thanks
    Think about it as a physical system - the top string is always under tension, so the bottom string is your "giveaway", so to say.
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    (Original post by aymanzayedmannan)
    Think about it as a physical system - the top string is always under tension, so the bottom string is your "giveaway", so to say.
    Ah so does the fact that the string is inextensible have something to do with that? Seeing as the bottom string can't stretch to make the top string go slack?
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    (Original post by Gome44)
    Because otherwise you would have levitating balls
    LOL


    basically the particle rotates at a contant radius so(as both strings are taut and inextensible) hence the faster it rotates the more the tension in the lower string so lowest possible angular velocity occurs when the tension in the lower string is zero
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    (Original post by PhyM23)
    Ah so does the fact that the string is inextensible have something to do with that? Seeing as the bottom string can't stretch to make the top string go slack?
    You can spot what Duke said from the equations of motions you have :yep: Probably the best answer you're looking for
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    (Original post by aymanzayedmannan)
    You can spot what Duke said from the equations of motions you have :yep: Probably the best answer you're looking for
    PRSOM

    Both answers were very helpful, thank you for your help
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    (Original post by PhyM23)
    PRSOM

    Both answers were very helpful, thank you for your help
    No worries! How's your M3 revision going by the way? I've just started past papers. Which paper is this from?
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    (Original post by aymanzayedmannan)
    No worries! How's your M3 revision going by the way? I've just started past papers. Which paper is this from?
    Sorry... Jan 2014 IAL.
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    (Original post by Zacken)
    Sorry... Jan 2014 IAL.
    oh noes, now I feel like I'm cheating xD
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    (Original post by aymanzayedmannan)
    oh noes, now I feel like I'm cheating xD
    Haha XD

    It's going well thanks! The questions seem to be quite repetitive, so I've been doing IAL papers since they seem harder than the GCE ones...

    How's your revision going, and how did you do with your January exams??
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    (Original post by PhyM23)
    Haha XD

    It's going well thanks! The questions seem to be quite repetitive, so I've been doing IAL papers since they seem harder than the GCE ones...

    How's your revision going, and how did you do with your January exams??
    Haha, that's good news for me this summer...

    They were alright. I flopped FP1 (bad day ) - got 86, but an A* in M2 + 100 in S1. A mixed bag, but I'd prefer S1 and FP1 the other way around.
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    (Original post by aymanzayedmannan)
    Haha, that's good news for me this summer...

    They were alright. I flopped FP1 (bad day ) - got 86, but an A* in M2 + 100 in S1. A mixed bag, but I'd prefer S1 and FP1 the other way around.
    Haha you're not alone! There's been a lot of talk about making exams harder in the UK because of these reforms etc. so I think we should both expect difficult papers...

    I wouldn't worry about FP1 seeing as it can't contribute to an A*. But I remember when I did FP1 last Summer - I left out an Argand diagram question and only realised when I got home...when I remembered I just put my head on my desk in dispair. I was really surprised I still got 88 in it though!

    But those are awesome results! You should have bags of confidence going into the Summer exams
 
 
 
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