Question

from a circle of diameter 20 CM a Sector 72 degrees is removed and the remaining portion of paper is made into a cone by joining its boundary radii find the volume of the cone​

Answer 1

Step-by-step explanation:

Slant height of cone = radius of circle from which sector is cut

l=10cm

Area length of 144

0

sector = 2π×radius×

360

0

144

0

= 2π×10×

360

144

=8π

Circumference of the base of cone = arc length = 8π cm

∴ 2πr=8π⇒r=4cm

h=

l

2

−r

2

=

10

2

−4

2

=

100−16

=

84

=2

21

∴ Volume of cone =

3

1

πr

2

h=

3

1

×

7

22

×4×4×2

21

=

21

704

21