Question

a sector contained an angle of 90 degree is cut from a circle of radius 42 cm and folded into a cone .then ,the curved surface area of cone is

Answer 1

If u fold the sector into a cone its slant height and perpendicular height will be equal

l= r

r = 42 ( acc. to the question)

CSA of cone = pi × l × r
CSA = 22/7 ×42×42
CSA = 5,554

so the curved surface area of cone is 5,554cm squ.


i hope it helps u buddy ✌✌

# JAI HIND

Answer 2

here is u r answer
..............

CSA of cone = area of sector
theta/360degreeπrsquare
=90°/360°×22/7×42×42

= 1386cm2