A hemispherical dome of a building needs to b | vedclass

Name: Exam Paper Generator | JEE NEET Paper Generator | Vedclass
Brand: Vedclass
Rating: 5 (35 reviews)

Question

(D) Since only the rounded surface of the dome is to be painted,we need to find the curved surface area of the hemisphere.Circumference of the base of

Vedclass · Accepted Answer

$Rs. 24640$

Vedclass · Answer

(D) Since only the rounded surface of the dome is to be painted,we need to find the curved surface area of the hemisphere.Circumference of the base of the dome $= 17.6 \, m$.Let the radius be $r$. Then,$2\pi r = 17.6$.$r = \frac{17.6}{2 	imes \pi} = \frac{17.6 	imes 7}{2 	imes 22} = 0.8 	imes 3.5 = 2.8 \, m$.Curved surface area of the hemisphere $= 2\pi r^2 = 2 	imes \frac{22}{7} 	imes 2.8 	imes 2.8 = 49.28 \, m^2$.Cost of painting $100 \, cm^2 = Rs. 5$.Since $1 \, m^2 = 10000 \, cm^2$,the cost of painting $1 \, m^2 = \frac{5}{100} 	imes 10000 = Rs. 500$.Total cost of painting $= 49.28 	imes 500 = Rs. 24640$.

$A$ hemispherical dome of a building needs to be painted. If the circumference of the base of the dome is $17.6 \, m$,find the cost of painting it,given the cost of painting is $Rs. 5$ per $100 \, cm^2$.

Similar Questions

$A$ metal pipe is $77\, cm$ long. The inner diameter of a cross section is $4\, cm$,and the outer diameter is $4.4\, cm$. Find its inner curved surface area. (in $, cm^{2}$)

Find the surface area of a sphere of radius $10.5 \, cm$.
Assume $\pi = \frac{22}{7}$. (in $, cm^{2}$)

$A$ cuboidal vessel is $10 \, m$ long and $8 \, m$ wide. How high must it be made to hold $380$ cubic metres of a liquid (in $, m$)?

The length,breadth,and height of a room are $5\, m$,$4\, m$,and $3\, m$ respectively. Find the cost of whitewashing the walls of the room and the ceiling at the rate of $Rs. 7.50$ per $m^2$.

The volume of a right circular cone is $9856 \, cm^3$. If the diameter of the base is $28 \, cm$,find the height of the cone. (in $, cm$)

Vedclass Test Series

Exam Paper Generator

Online Exam Module