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The height and radius of base of a metal...

The height and radius of base of a metallic cone are 27 cm and 16 cm respectively .It is melted and recast into a sphere .Find the radius and curved surface of the sphere.

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To solve the problem step by step, we need to find the radius and the curved surface area of a sphere formed by melting a metallic cone. ### Step 1: Identify the given values - Height of the cone (h) = 27 cm - Radius of the base of the cone (r) = 16 cm ### Step 2: Calculate the volume of the cone The formula for the volume of a cone is given by: \[ V_{cone} = \frac{1}{3} \pi r^2 h \] Substituting the values of r and h: \[ V_{cone} = \frac{1}{3} \pi (16)^2 (27) \] Calculating \(16^2\): \[ 16^2 = 256 \] Now substituting back: \[ V_{cone} = \frac{1}{3} \pi (256) (27) \] Calculating \(256 \times 27\): \[ 256 \times 27 = 6912 \] Thus, \[ V_{cone} = \frac{1}{3} \pi (6912) = 2304 \pi \, \text{cm}^3 \] ### Step 3: Set the volume of the cone equal to the volume of the sphere When the cone is melted and recast into a sphere, the volume of the sphere (V_sphere) will be equal to the volume of the cone: \[ V_{sphere} = \frac{4}{3} \pi R^3 \] Setting the volumes equal: \[ 2304 \pi = \frac{4}{3} \pi R^3 \] We can cancel \(\pi\) from both sides: \[ 2304 = \frac{4}{3} R^3 \] ### Step 4: Solve for \(R^3\) Multiplying both sides by \(\frac{3}{4}\): \[ R^3 = 2304 \times \frac{3}{4} \] Calculating \(2304 \times \frac{3}{4}\): \[ 2304 \times \frac{3}{4} = 1728 \] Thus, \[ R^3 = 1728 \] ### Step 5: Find the radius \(R\) To find \(R\), we take the cube root of 1728: \[ R = \sqrt[3]{1728} \] Calculating the cube root: \[ R = 12 \, \text{cm} \] ### Step 6: Calculate the curved surface area of the sphere The formula for the curved surface area (CSA) of a sphere is: \[ CSA = 4 \pi R^2 \] Substituting the value of \(R\): \[ CSA = 4 \pi (12)^2 \] Calculating \(12^2\): \[ 12^2 = 144 \] Thus, \[ CSA = 4 \pi (144) = 576 \pi \, \text{cm}^2 \] ### Final Answers - Radius of the sphere \(R = 12 \, \text{cm}\) - Curved surface area of the sphere \(CSA = 576 \pi \, \text{cm}^2\)

To solve the problem step by step, we need to find the radius and the curved surface area of a sphere formed by melting a metallic cone. ### Step 1: Identify the given values - Height of the cone (h) = 27 cm - Radius of the base of the cone (r) = 16 cm ### Step 2: Calculate the volume of the cone The formula for the volume of a cone is given by: ...
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