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    a child, mass 30kg slides down 5m down a playground slide inclined at 40 to the horizontal. Calculate the potential energy lost.

    I did 30x9.8x 5sin40 = 1095J

    However, answer sheet says its 945J?

    Where have I gone wrong?
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    Edit: cocked it up, my apologies. Is there any mention of a resistive force etc?
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    (Original post by JumpingJonny)
    sin 40 = 5/h therefore h = 5/sin40

    Try using that and see how it goes
    That is wrong.
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    you must take friciton into account
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    (Original post by SilverstarDJ)
    a child, mass 30kg slides down 5m down a playground slide inclined at 40 to the horizontal. Calculate the potential energy lost.

    I did 30x9.8x 5sin40 = 1095J

    However, answer sheet says its 945J?

    Where have I gone wrong?
    5sin(40) \times 30 \times 9.8 = 945 J

    Check your calculator skillzzz
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    When I put that in my calculator it comes out as 944.89J Check you have entered it correctly
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    (Original post by gilbo)
    That is wrong.
    Yeah I realised that once I had written it, hence the edit, the OP is actually correct, he just hasnt calculated it right.
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    (Original post by gilbo)


    Check your calculator skillzzz
    lol!!
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    aaah it's in radians and not degrees! Thanks.
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    (Original post by SilverstarDJ)
    aaah it's in radians and not degrees! Thanks.
    HAHA textbook schoolboy error.
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    Why The Hell Have I Been Negged?????? That Bloody Coward Didnt Even Put His Name!!!!

    Is It A Crime Helping???

    I Swear The Guy Who Negged Me Will Rot In Hell!!! **** You *******!!!
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    and i have been negged again.....as if i really care
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    3 negs on a single day....that must be a record

    well if the person negging me thinks that he is sooo smart or that i am angry....then he is wrong. it doesnt make a difference to me.

    all i can say is that if you want to neg me, then just leave your name so that i can rep you....may God bles your soul
 
 
 
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