The inner diameter of circular well is 3.5 m. It is 10m deep. Its inner curved surface area in m² is:
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Explanation:
The inner curved surface area (CSA) of a circular well (cylinder) is given by the formula:
CSA = 2πrh,
where:
– r is the radius of the circular base,
– h is the depth (or height) of the well.
From the problem:
– The inner diameter of the well is 3.5 m, so the radius (r) is:
r = Diameter / 2 = 3.5 / 2 = 1.75 m,
– The depth (h) of the well is 10 m.
Substitute the values of r = 1.75 m and h = 10 m into the formula:
CSA = 2πrh.
Using π ≈ 22/7 for calculation:
CSA = 2 × (22/7) × 1.75 × 10.
Simplify step by step:
CSA = 2 × (22/7) × 17.5,
CSA = 2 × 22 × 2.5,
CSA = 110 m².
Thus, the inner curved surface area of the well is 110 m², which corresponds to option b) 110.
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