A cone has a height of 24 cm and its base has a radius of 6 cm. If the cone is horizontally cut into two segments 12 cm from the base, what would the surface area of the bottom segment be?

1 Answer
Jun 28, 2018

Total surface area of bottom segment is 491.11 sq.cm.

Explanation:

The cone is cut at 12 cm from base, So upper radius of the

frustum of cone is r_2=(24-12)/24*6=3 cm ; slant ht:

l=sqrt(12^2+(6-3)^2)=sqrt(153)~~ 12.37 cm.

Top surface area A_t=pi*3^2~~ 28.274 sq.cm

Bottom surface area A_b=pi*6^2~~113.1 sq.cm

Slant Area A_s=pi*l*(r_1+r_2)=pi*12.37*(6+3)

~~349.74 sq.cm.

Total surface area of bottom segment

=A_t+A_b+A_s=28.27+113.1+349.74~~491.11 (2dp)

sq.cm [Ans]