a circus tent is cylindrical up to a height of 15 m and conical above it if the diameter of the base is 56m and the total height of the 60m find the total Canvas used in making the tent
Answers
Answer:
Given:
Diameter = 56 cm = 0.56m
Height of cylindrical part = 6 m
Total Height = 27 m
∵ Diameter = 0.56 m
∴ Radius = 1/2 × 0.56 m = 0.28 m
Also,
Height of conical part = Total height – Height of cylindrical part
⇒ Height of conical part = 27 m – 6 m
⇒ Height of conical part (h) = 21 m
Clearly,
Total Surface Area of canvas = Curved surface area of cylinder + Curved surface area of cone …(1)
Curved surface area of cylinder = 2πrh
⇒ Curved surface area of cylinder = 2 × 22 × 0.04 ×6
⇒ Curved surface area of cylinder = 10.56 m2
Curved surface area of cone = πrl …(2)
(where, l = slant height)
To find l,
l2 = r2 + h2
⇒ l2 = 0.282 + 212
⇒ l2 = 0.0784 + 441
⇒ l2 = 441.0784
⇒ l = √441.0784 ~ 21
⇒ l = 21 cm
Put the value of l in (2),
⇒ Curved surface area of cone = 22 × 0.28 × 3
⇒ Curved surface area of cone = 18.48 cm2
Putting all the values in (1),
Total Surface Area of remaining solid = 10.56 cm2 + 18.48 cm2
⇒ Total Surface Area of remaining solid = 29.04 cm2
Hence, Total Surface Area of canvas = 29.04 cm2