A closed cylindrical tank of radius 7 m and height 3 m is made from a sheet of metal. How much sheet of metal is required?
Solution:
Let's construct a diagram according to the given question.
Height of the cylindrical tank (h) = 3 cm
Radius of the cylindrical (r) = 7 cm
Lateral surface area of the cylinder = 2πrh = 2 × 22/7 × 7 × 3 = 132 m² …(1)
Area of circlular base = Area of top = πr²
= 22/7 × 7 m × 7 m = 154 m² …(2)
The metal sheet required will be equal to the total surface area of the cylinder.
Total surface area of cylinder = Lateral surface area of the cylinder + Area of two circular end
= 2πrh + 2πr²
= 132 m² + 308 m² [substituting values from (1) and (2)]
= 440 m²
Thus, the amount of metal sheet required will be 440 m².
☛ Check: NCERT Solutions for Class 8 Maths Chapter 11
Video Solution:
A closed cylindrical tank of radius 7 m and height 3 m is made from a sheet of metal. How much sheet of metal is required?
Maths NCERT Solutions Class 8 Chapter 11 Exercise 11.3 Question 7
Summary:
A closed cylindrical tank of radius 7 m and height 3 m is made from a sheet of metal. 440 m² sheet is required.
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