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    i cant seem to get the right answer for this question "_" i'm probably making a very basic mistake but i just cant see it lol

    A particle travels at a constant speed around a circle of radius r with a centripetal acceleration a. what is the time taken for ten complete rotations?
    if:
    v=\frac{2 \pi r }{T}

    T=\frac{2 \pi r }{v}

    and if
    a= \frac{ v^{2} }{r}

    v=\sqrt{ar}
    so substitute for V

    T= \frac{2 \pi r }{\sqrt{ar}}

    T= \frac{2 \pi }{\sqrt{a}}
    for 10 revolutions so times both sides by 10
    10T=\frac{20 \pi }{\sqrt{a}}
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    anybody?
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    (Original post by cuckoo99)
    i cant seem to get the right answer for this question "_" i'm probably making a very basic mistake but i just cant see it lol

    A particle travels at a constant speed around a circle of radius r with a centripetal acceleration a. what is the time taken for ten complete rotations?
    if:
    v=\frac{2 \pi r }{T}

    T=\frac{2 \pi r }{v}

    and if
    a= \frac{ v^{2} }{r}

    v=\sqrt{ar}
    so substitute for V

    T= \frac{2 \pi r }{\sqrt{ar}}

    T= \frac{2 \pi }{\sqrt{a}}
    The line above is not correct. r does not cancel.
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    I found this hard tooo
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    \sqrt{r}\neq r therefore the r doesn't cancel.
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    lolz what a stupid mistake ye i found the answer to be 20 \pi  \sqrt{\frac{r}{a} }
 
 
 
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