2. The slant height of a right circular cone is
10 m and its height is 8 m. Find the area of
its curved surface.
A) 30 m2
B) 40 m2
C) 60 m2
D) 80 m2
Answers
Given:
The slant height of a right circular cone is 10m and its height is 8m.
To find:
The area of its curved surface area.
Explanation:
We know that formula of the slant height: l²= r² + h²
We have,
- Slant height of cone,l= 10m
- Height of the cone,h= 8m
→ 10² = r² + 8²
→ 100m² = r² + 64m²
→ r² = 100m² -64m²
→ r² = 36m²
→ r = √36m²
→ r = 6m
We know that formula of the curved surface area of cone: πrl [sq.units]
→ π × 6m × 10m
→ 60π m²
Thus,
The curved surface area of cone is 60π m².
A N S W E R »
A) 30 m2
B) 40 m2
C) 60 m2 ✓
D) 80 m2
The slant height of a right circular cone is 10m and its height is 8m.
To find:
The area of its curved surface area.
By using the formula of the slant height: l²= r² + h²
We have,
Slant height of cone,l= 10m
Height of the cone,h= 8m
→ 10² = r² + 8²
→ 100m² = r² + 64m²
→ r² = 100m² -64m²
→ r² = 36m²
→ r = √36m²
→ r = 6m
We know that formula of the curved surface area of cone: πrl [sq.units]
→ π × 6m × 10m
→ 60π m²