Question

a storage tank consists of a circular cylinder with a hemisphere stuck on either side. if the external diameterof the cylinder be 1.4m and its length be 8m. find the cost of painting it on the outside at a rate of 20/m square

Answer 1

Tsa of cylinder = 2 pi r( r+h) according to the question Tsa of given cylinder 2 ❌ 22/7❌ 0.7 ( 0.7+ 8)= 4.4❌ 8.7= 42.68sq.m Cost of painting cylinder at rate of 20/sq.m= 42.68❌ 20 = Rs. 853.6

Answer 2

Answer:

Rs.827.2

Step-by-step explanation:

Diameter of cylinder = 1.4 m

Radius of cylinder = $\frac{1.4}{2} = 0.7 m$

Height of cylinder = 8 m

Curved surface area of cylinder = $2 \pi r h$

                                                    =$2 \times \frac{22}{7} \times 0.7 \times 8$

                                                    =$35.2 m^2$

We are given that a storage tank consists of a circular cylinder with a hemisphere stuck on either side

Radius of hemisphere = 0.7 m

Curved surface area of hemisphere = $2 \pi r^2$

So, Curved surface area of 2 hemisphere =  $2(2 \times \frac{22}{7} \times 0.7^2)$

                                                                     =  $6.16 m^2$

Outer surface area of tank = $35.2 m^2+6.16 m^2=41.36 m^2$

Cost of painting 1 sq.m. = Rs.20

Cost of painting 41.36 sq.m. = $20 \times 41.36=827.2$

Hence the cost of painting is Rs.827.2