A solid toy is in the form of a hemisphere surmounted by a right circular come. Height of the cone is 2 cm and the diameter of the base is 4 cm. /if a right circular cylinder circumscribes the toy, find how much more space it will cover.

Given radius of cone, cylinder & hemisphere (r) = 4/2 = 2 cm


Height of cone (l) = 2 cm


Height of cylinder (h) = 4 cm


Volume of cylinder = h = (4) cm …….. (1)


Volume of cone =


=


= × 4 × 2 cm ………………. (2)


Volume of hemisphere =


=


= …………….. (3)


So remaining volume of cylinder when toy is instead to it



= eq.(1) – eq.(2) + eq.(3)


= π(2)2(4) – ( × π × 8)


= 16π - π (4+8)


= 16π – 8π


= 8π cm3


So remaining volume of cylinder when toy is instead to it = 8π cm3


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