A cylinder of height 8 cm and radius 6 cm is melted and converted into 3 cones of the same radius and height that of cylinder. Determine the total curved surface area of cones.
Answer & explanation
Correct answer: option 1
We know that,
The curved surface area of a cone = πrl
l = \(\sqrt {h^2 + r^2}\)
Height of the cylinder = 8cm
Radius of the cylinder = 6cm
Now, r = 6 cm , h = 8 cm
= l = \(\sqrt {8^2 + 6^2}\) = 10 cm
We have moulded 3 cones from a cylinder =
Total curved surface area of cone = 3 × (π × r × l) = 3 × (π × 6 × 10) = 180 π cm2