What will be the curved surface area of cone whose height is 8 cm and radius is 6 cm?
1. 1530/7 square cm
2. 1320/7 square cm
3. 1120/7 square cm
4. 1100/7 square cm
1. 1530/7 square cm
2. 1320/7 square cm
3. 1120/7 square cm
4. 1100/7 square cm
Correct Answer – Option 2 : 1320/7 square cm
Given:
The height and radius of cone is 8 cm and 6 cm respectively
Formula used:
Curved surface area of cone = π r l
Slant height = √ (h)2 + (r)2
Where r is radius, h is height and l is the slant height of cone
Calculation:
To calculate the curved surface area first we have to calculate the slant height
∴ Slant height = √ (8)2 + (6)2 = √100 = 10 cm
Now, curved surface area of cone = π r l = (22/7) × 6 × 10 = 1320/7 square cm
Hence, option (2) is correct