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    This is the question:

    -----------------------------------

    The head of a piston moves with SHM of amplitude 0.1root 3m about a mean position O. How far from O is the head of the piston when it is travelling with a speed equal to half its maximum speed.

    -------------------------------------------------------------

    Is there really enough information in the question to be able to do this?
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    (Original post by maggiehodgson)
    This is the question:

    -----------------------------------

    The head of a piston moves with SHM of amplitude 0.1root 3m about a mean position O. How far from O is the head of the piston when it is travelling with a speed equal to half its maximum speed.

    -------------------------------------------------------------

    Is there really enough information in the question to be able to do this?
    AFAIK, yes. Why do you think there isn't? Call the maximum speed v. Then v^2 = w^2 \times 0.1^2 \times 3

    Then you want to find x s.t \frac{1}{2}\sqrt{w^2 \times 0.1^2 \times 3} = \sqrt{w^2 (0.1^2 \times 3 - x^2)} (or something vaguely like that)
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    (Original post by Zacken)
    AFAIK, yes. Why do you think there isn't? Call the maximum speed v. Then v^2 = w^2 \times 0.1^2 \times 3

    Then you want to find x s.t \frac{1}{2}\sqrt{w^2 \times 0.1^2 \times 3} = \sqrt{w^2 (0.1^2 \times 3 - x^2)} (or something vaguely like that)
    AFAIK??
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    (Original post by TeeEm)
    AFAIK??
    As far as I know
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    (Original post by Zacken)
    As far as I know
    danke
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    (Original post by Zacken)
    AFAIK, yes. Why do you think there isn't? Call the maximum speed v. Then v^2 = w^2 \times 0.1^2 \times 3

    Then you want to find x s.t \frac{1}{2}\sqrt{w^2 \times 0.1^2 \times 3} = \sqrt{w^2 (0.1^2 \times 3 - x^2)} (or something vaguely like that)
    Yes, you are dead right. I just hadn't gone far enough with my own work to see how to eliminate w.
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    (Original post by maggiehodgson)
    Yes, you are dead right. I just hadn't gone far enough with my own work to see how to eliminate w.
    Great. Yeah, that's always a thing with these questions, lots of terms cancel out. Especially in stuff like circular motion where mass cancels out at the very last step and you breathe a sigh of relief.
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    (Original post by Zacken)
    Great. Yeah, that's always a thing with these questions, lots of terms cancel out. Especially in stuff like circular motion where mass cancels out at the very last step and you breathe a sigh of relief.
    Thanks for the warning - I think that's the next chapter. Oh Joy!
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    (Original post by maggiehodgson)
    Thanks for the warning - I think that's the next chapter. Oh Joy!
    It's a fun one, to be honest. The 'show that' questions are a free 6/8 marks. Enjoy it, make sure you know your energy principles well.
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    (Original post by Zacken)
    It's a fun one, to be honest. The 'show that' questions are a free 6/8 marks. Enjoy it, make sure you know your energy principles well.
    Believe it or not I'm only doing mechanics for fun. I'm a mature student, self teaching. I did A level - also self taught - two years ago. Having been out of education and exams for many many years I almost scared myself to death and wished I'd never put myself through the terror of the exam room. I swore I'd never do such a thing ever again.

    So mechanics for fun. I must be a masochist.
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    (Original post by maggiehodgson)
    Believe it or not I'm only doing mechanics for fun. I'm a mature student, self teaching. I did A level - also self taught - two years ago. Having been out of education and exams for many many years I almost scared myself to death and wished I'd never put myself through the terror of the exam room. I swore I'd never do such a thing ever again.

    So mechanics for fun. I must be a masochist.
    I can relate with the self-teaching thing, seems like you're doing good, from what I've seen of you so far! So keep at it. Being a masochist is fun. Are you planning on doing M4/5 as well?
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    (Original post by Zacken)
    I can relate with the self-teaching thing, seems like you're doing good, from what I've seen of you so far! So keep at it. Being a masochist is fun. Are you planning on doing M4/5 as well?

    Well. We'll see. At the current rate of progress I might not even get to the end of M3 hahahha.

    However, if I do, given that beating my head on a brick wall is preferable to daytime tv/housework/statistics/decision mats etc, then probably yes.

    Thanks for the encouragement. Without TSR it would have to be daytime TV and housework. God forbid.
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    (Original post by maggiehodgson)
    Thanks for the encouragement. Without TSR it would have to be daytime TV and housework. God forbid.
    Ah, that's what we're for! :yep:
 
 
 
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