A conical structure and a hemispherical structure share the same base radius r. If the curved surface area of the cone is equal to the curved surface area of the hemisphere, express the slant height l of the cone in terms of r.
Correct Answer :
l = 2r
Solution :
Correct Answer: l = 2r
Step-by-step explanation:
Let r be the common base radius of the conical structure and the hemispherical structure, and let l be the slant height of the cone.
The curved surface area (CSA) of a cone is calculated using the formula:
The curved surface area (CSA) of a hemisphere is calculated using the formula:
According to the problem statement, the curved surface area of the cone is equal to the curved surface area of the hemisphere:
Substituting the respective formulas into the equation:
To find the slant height l in terms of r, divide both sides of the equation by πr (since radius r > 0 and π ≠ 0):
Simplifying the right-hand side:
Therefore, the slant height l of the cone expressed in terms of r is l = 2r.
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