Mathematics

A sector of a circle radius 8cm subtends and and angle 90°a at the centre of a circle. If the sector is folded without overlap to form the curved surface of a cone, find the 1. Base radius 2. Height 3. Volume of the cone.

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  1. s = rθ so the circumference of the base of the cone is 8*π/2 = 4π
    Thus the radius of the base is 4π/2π = 2 (1/4 the radius of the original circle)
    The slant height is the original circle radius.
    so the height of the cone is √(8^2-2^2) = √60
    as always, the volume v = 1/3 πr^2 h

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    oobleck
  2. I don't like ur answer
    it's not well explanatory

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