Question

A piece of paper is in the
form of a sector, making
an angle . The paper is
rolled to form a right
circular cone of radius 5
cm and height 12 cm. Then
the value of 'e' is in
radians)
plz say​

Answer 1

Answer:

$10\pi \div 13$

Step-by-step explanation:

r=5

h=12

area of sector =1/2 × angle × r²

surface area of cone = pi × r × l

l²= r² + h²

l=13

1/2 × angle × R²=pi × r × l

here R is radius of sector which is equal to l

R=13

1/2 × angle × 13² = pi × 5 ×13

angle =10 pi/13