Question

. An Ice cream in the shape of a cone is surmounted by a hemisphere. Find the volume of ice cream(in form of π) if, both radius of circular base of cone and hemisphere are 1Cm each and height of cone is 1 Cm .

(a) 4π

( b) π

(c) 3π

(d)none of these

​

Answer 1

•Volume of cone +volume of hemisphere = volume of ice-cream

=> 1/3 πr²h + 2/3 πr³

=> 1/3π + 2/3π

=> π

$\huge\bf\underline{\underline{\pink{A}\orange{N}\blue{S}\red{W}\green{E}\purple{R}}}$

b) π

Answer 2

Given :

Area of Circular Card Board is 154 cm².

To Find :

Circumference of Base in the form of π .

Solution :

Firstly we will Find the Radius of Board :

Using Formula :

\longmapsto\tt\boxed{Area\:of\:Circle=\pi{{r}^{2}}}⟼

AreaofCircle=πr

2

Putting Values :

\longmapsto\tt{154=\dfrac{22}{7}\times{{r}^{2}}}⟼154=

7

22

×r

2

\longmapsto\tt{154\times{7}=22\times{{r}^{2}}}⟼154×7=22×r

2

\longmapsto\tt{1078=22\:{r}^{2}}⟼1078=22r

2

\longmapsto\tt{\cancel\dfrac{1078}{22}={r}^{2}}⟼

22

1078

=r

2

\longmapsto\tt{\sqrt{49}=r}⟼

49

=r

\longmapsto\tt\bf{7\:cm=r}⟼7cm=r

Radius of Circular Card Board is 7 cm .

Now ,

\longmapsto\tt{Radius=7\:cm}⟼Radius=7cm

Using Formula :

\longmapsto\tt\boxed{Circumference\:of\:Circle=2\pi{r}}⟼

CircumferenceofCircle=2πr

Putting Values :

\longmapsto\tt{2\times{\pi\times{7}}}⟼2×π×7

\longmapsto\tt\bf{14\:\pi\:cm}⟼14πcm

So , The Circumference of Circular Card board is 14 π cm

Option a)14 π cm is Correct