a) The circumference of the base of the cone is the same length as the curved edge of the sector.
Circumference of the base of the cone = 2πr
Curved edge of the sector = 2π(8) (since the radius of the sector is 8cm) = 16π cm
Setting them equal to each other:
2πr = 16π
r = 8 cm
Therefore, the radius of the cone is 8 cm.
b) The angle at the vertex of the cone is the same as the angle of the sector, which is 156°. The vertical angle is always twice the angle at the apex of the cone.
Vertical angle = 2(156°) = 312°
Therefore, the vertical angle of the cone is 312°.
We are given a sectorwith radius 8cm and an angle of 156°. The sector is bent form a right cone
a) Calculate the radius of the cone
b) vertical angle of the cone
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