A paper cone has a base diameter of 8cm and a height of 3cm(a) use Pythagoras theorem to calculate it's slant height (b)if the cone is cut and opened out into the sector of a circle what is the angel of the sector

Answer 1

Make a sketch to see that r = 5, h = 3
then s^2 = 5^2 + 3^2 = 34
slant height = √34 cm

circumference of base of cone
= 2π(5) = 10π cm
This becomes the arc-length in a circle of circumference of 2π√34

let the angle of the sector be Ø

arc = rØ
10π = √34Ø
Ø = 10π/√34 radians
= appr 5.388 radians or appr 308.7°

Answer 2

calculate the curved surface area of the cone in terms of pi

Answer 3

a is 5cm b is 288 degree

Answer 4

How is b=288?

Answer 5

i don't know how to draw the sketch

Answer 6

Abeg i no understand how una tey do this one ooo pls expantiate better o ti daru momi loju nsin biko na beg i de beg o mathematician