Question

the diameter of the base of a right circular cone is 21 cm and it's Hight is 14 cm . it's curved surface area is​

Answer 1

${\tt { {\underline{\underline{\huge{ Answer:}}}}}}$

$total curved surface area = 924cm$

Step-by-step explanation:

diameter is 21 cm

diameter $=$ $\frac{radius}{2}$

so,radius will be 10·5 cm

height is 14 cm

$formula for total curved surface area = \pi r(l+r)$

$\pi$ $=$ 3·14

r $=$ radius

l $=$ slant height

$formula for slant height (l) =$$\sqrt{ (10.5)^{2} +(14)^{2} }$

$l = \sqrt{(110.25) + (196) }$

$l = \sqrt{306.25}$

$l = 17.5 cm$

so, total curved surface area will be

$\pi r(l+r) = 3.14*10.5*(17.5+10.5)$

$= 3.14*10.5*28 cm$

total curved surafe area 924cm