C4 rotation help

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  1. alexlct054's Avatar
    • Junior Member
    • Posts: 29
    C4 rotation help
    For the Question 10(iii), Find the capacity of the vase in litres
    I know the formula is the the integral of pi*(y+4) between 12 and 0.
    After solving this, I get the ans of 120*pi cm^3
    am I right or not?
    however, I don't know how to express 120*pi cm^3 in litres, ( the ans is 3 litres). Can anyone help me to solve this pls? Thx for ur help..
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  2. ghostwalker's Avatar
    • Outcast of Imrryr
    • Location: CA13
    Re: C4 rotation help
    (Original post by alexlct054)
    For the Question 10(iii), Find the capacity of the vase in litres
    I know the formula is the the integral of pi*(y+4) between 12 and 0.
    After solving this, I get the ans of 120*pi cm^3
    am I right or not?
    You've integrated correctly, however you've not taken into account that each unit represents 2 cm.


    however, I don't know how to express 120*pi cm^3 in litres, ( the ans is 3 litres). Can anyone help me to solve this pls? Thx for ur help..
    1000 cm^3 = 1 litre. And take it from there; with your corrected value.
  3. han.b's Avatar
    • New Member
    • Posts: 2
    Re: C4 rotation help
    ok, i get 120*pi units ^3 not cm^3

    because it says that each unit of x and y represents 2cm so we have '120*pi * 8 cm^3'

    8 because 2^3 = 8

    so thats 960*pi

    now 1000cm^3 = 1 litre

    so 960*pi / 1000 = 3.015... litres and round that up to 3 litres

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