Question

rajesh has been given a task of designing a boiler of ntpc. boiler consist of a cylinder part in middle and 2 Hemispherical part its both end.the cross section pf boiler given below .length of the cylindrical part is 3times of radius of hemisphere part.
Ans the below questions with the workouts plzzzz.​

Answer 1

Given:

A boiler made of cylindrical part in middle and 2 hemispherical parts at its both ends in figure given

Radius of hemisphere = r

Height of cylinder = 3r

Solution:

(i) Answer: (b)6πr²

Explaination:

We are asked to find the surface area of cylindrical part

Lateral surface area of cylinder is given by $2{\pi}rh$

Here r = radius of cylinder = $r$

         h = height of cylinder = $3r$

surface area of cylinder = $2{\pi}rh$

                                        = $2{\pi}r(3r)$

surface area of cylinder = $6{\pi}r^{2}$

(ii) Answer:  (d) 10πr²

Explaination:

We are asked to find the total surface of area of boiler it is given by                  2(curved surface area of hemisphere) + (Lateral surface area of cylinder)

So Total surface area = $2(2{\pi}r^{2} )+(6{\pi}r^{2})$

                                    = $10{\pi}r^{2}$

(iii) Answer:  (c)13/3 πr³

Explaination:

Volume of boiler= 2(volume of hemisphere)+volume of cylinder

                           = $2(\frac{2}{3}{\pi}r^{3})+{\pi}r^{2}h$

                           =  $(\frac{4}{3}{\pi}r^{3})+{\pi}r^{2}(3r)$

                           = $(\frac{4}{3}{\pi}r^{3})+3{\pi}r^{3}$

                           = $(\frac{4}{3}{\pi}r^{3})+\frac{9}{3} {\pi}r^{3}$

Volume of boiler= $(\frac{13}{3}{\pi}r^{3})$

(iv)Answer:  13/30 (r)

Explaination:

We are asked to find the ratio of volume of boiler to the surface area of boiler

Ratio = $\frac{Volume of boiler}{Surface area of boiler}$

         = $\frac{\frac{13}{3}{\pi}r^{3} }{10{\pi}r^{2} }$

Ratio  =$\frac{13}{30}r$

Answer 2

Step-by-step explanation:

rajesh has been given a task of designing a boiler of ntpc. boiler consist of a cylinder part in middle and 2 Hemispherical part its both end.the cross section pf boiler given below .length of the cylindrical part is 3times of radius of hemisphere part.

Answers in the image

Hope it helps!! :>