Question

A heap of rice is in the form of a cone diameter 12 cm and height 8 cm .how much canvas cloth is required to cover the heap? need the answer as soon as possible please help

Answer 1

Answer:

188.5

Explanation:

Given :

• Diameter = 12cm
• Radius = 12/2 => 6
• Height = 8cm

To Find :

How much canvas cloth is required to cover the heap?

Solution :

To begin with we need to find slant height of the cone, which is determined by using Pythagoras, since the cross section is a right triangle.

$\rm{}l^2=h^2+r^2$

$\rm{}l^2=8^2+6^2$

$\rm{}l^2=64+36$

$\rm{}l^2=100$

$\rm{}\sqrt{(l^2)}=\sqrt{100}$

$\rm{}l= 10$

Covered surface area => π × r × l

$\rm{}CSA=\pi\times r \times l$

$\rm{}CSA=\dfrac{22}{7}\times 6 \times 10$

$\rm{}CSA=\dfrac{1320}{7}$

$\rm{}CSA= 188.5$

(Figure in attachment)

Answer 2

$\bf \huge{ \underline { \underline{ \red{ answer }}}}$

$\bf \bold{here \: d = 12 \: cm}$

$\bf \bold{ \: so \: \: \: r = \frac{12}{2} = 6m}$

$\bf \bold{h = 8 \: m}$

$\bf \green{ \: required \: volume = \frac{1}{3} \pi \: {r}^{2} h}$

$\bf \green{ \implies \: \frac{1}{3} \times \frac{22}{7} \times 6 \times 6 \times 8}$

$\bf \green{ \implies \: 301.71 {m}^{3} }$

$\bf \purple{let \: \: l \: \: be \: the \: slant \: height \: of \: cone}$

$\bf{ \implies \: {l}^{2} = {r}^{2} + {h}^{2} }$

$\bf{ \implies {l}^{2} = {6}^{2} + {8}^{2} }$

$\bf{ \implies {l}^{2} = 36 + 64}$

$\bf{ \implies {l}^{2} = 100}$

$\bf{ \implies \: l = 10 \: m}$

To cover a heap we need curved surface area of cone .

$\bf \pink{curved \: surface \: area \: of \: cone = \pi \: rl}$

$\bf \pink{ \implies \: \frac{22}{7} \times 6 \times 10}$

$\bf \pink{ \implies188.57 {m}^{2} }$

$\bf \fbox \red{ \: required \: volume \: is \: 301.71 {m}^{3} \: \: \: \: \: and \: \: \: \: \: canvas \: cloth \: required \: to \: cover \: heap \: is \: 188.57 {m}^{2} }$