Question

A sector of a circle of radius 15 cm has an angle of 120". It is rolled up so that the two
binding radil are joined together to form a cone. Find the volume of the cone​

Answer 1

Step-by-step explanation:

Hola there

LET WE CUT OUT THE SECTOR FROM THE CIRCLE.

LENGTH OF THE ARC= 120/360 X 2 PIE r = 1/3  X  2 PIE 15  =  10 PIE.

NOW, THE SECTOR IS ROLLED TO MAKE A CONE.

RADIUS OFTHE CIRLE= SLANT HEIGHT OF THE CONE= 15 UNITS.

LENGHT OF THE ARC= CIRCUMFERENCE OF THE BASE OF THE CONE = 10 PIE.

2 PIE r = 10 PIE.

RADIUS OF THE CONE= 5 UNITS.

HEIGHT OF THE CONE= h

h2 = 152 - 52 = 200,  h= 10 * root 2.

VOLUME OF THE CONE = 1/3 PIE r2 h

(TAKE VALUE OF root 2 =1.414)

= 1/3  X 22/7  X  5  X  5  X  10*root 2

= 22  X  25 X  14.14

  3  X  7

= 370.33 cm3

NICE QUESTION........