An oil funnel of tin sheet consists of a cylindrical portion of length 1o cm long attached to a frustum of cone. if the total height of the funnel is 22cm and the diametre of the cylindical portion be 8 cm and the diamter of the top of the funnel be 18cm find the area of tin required to make the funnel
Let and ( r1 > r2) be the radii of ends of the frustum of a cone.
be the slant height of the frustum, height of the frustum and height of the cylinder.
Radius of upper circular end of frustum part,
Radius of lower circular end of frustum part=radius of circular end of cylindrical part,
Height of frustum part,
Height of cylindrical part=10 cm
Slant height of frustum part ,
Area of tin sheet required = Curved Surface Area of frustum part+Curved Surface Area of cylindrical part