A tent is in the form of a cylinder of diameter 20 m and height 2.5 m, surmounted by a cone of equal base and height 7.5 m.Find the capacity of the tent and the cost of the canvas at Rs.100 per square metre.
Solution:
As per the parameters given in the question, we have
Diameter of the cylinder = 20 m
Radius of the cylinder = 10 m
Height of the cylinder (say h1) = 2.5 m
Radius of the cone = Radius of the cylinder (say r) = 15 m
Height of the Cone (say h2) =7.5 m
Let us consider L as the slant height of the Cone, then
L = √r2+h22
= √152+7.52=12.5 m
Volume of the cylinder, V1=πr2h1=π(10)2×2.5=250π m3
Volume of the Cone, V2=13πr2h2=13×227×(10)2×7.5=250π m3
Therefore, The total capacity of the tent = volume of the cylinder + volume of the cone = V1 + V2
V = 250 π + 250 π
V = 500 π m3
Hence, the total capacity of the tent = V = 4478.5714 m3
The total area of the canvas required for the tent is S = 2 πrh1 + πrL
S = 2(π)(10)(2.5) + π(10)(12.5)
S = 550 m2
Therefore, the total cost of the canvas is (100) (550) = Rs. 55000