a) What is the volume of a solid metal cylinder of height 4 centimetres and radius 5 centimetres? b) This solid is melted and recast in to 5 cones of equal height and radius 2 centimetres. Find the height of such a cone.
Open in App
Solution
(a) Height of cylinder, h=4cm Radius of cylinder, r=5cm Volume of cylinder =πr2h =3.14×52×4cm3 =314cm3 (b) Radius of re-casted cone, r=2cm Let, height of re-casted cone =h Volume of each cone =3145cm3=62.8cm3 Volume of cone =13πr2h
62.8=13×3.14×(2)2×h
h=62.8×34×3.14cm h=15cm Height of the cone is 15cm.