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A right circular cone is 8 cm high and r...

A right circular cone is 8 cm high and radius of its base is 2 cm .The cone is metted and recaset in to a sphere. Determine the diameter of the sphere.

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To solve the problem step by step, we will calculate the diameter of the sphere formed by melting the cone. ### Step 1: Find the volume of the cone The formula for the volume \( V \) of a right circular cone is given by: \[ V = \frac{1}{3} \pi r^2 h \] where \( r \) is the radius of the base and \( h \) is the height of the cone. Given: - Height \( h = 8 \) cm - Radius \( r = 2 \) cm Substituting the values into the formula: \[ V = \frac{1}{3} \pi (2)^2 (8) \] Calculating this: \[ V = \frac{1}{3} \pi (4)(8) = \frac{32}{3} \pi \text{ cm}^3 \] ### Step 2: Set the volume of the sphere equal to the volume of the cone When the cone is melted and recast into a sphere, the volume of the sphere \( V_s \) will be equal to the volume of the cone \( V_c \). The formula for the volume \( V_s \) of a sphere is: \[ V_s = \frac{4}{3} \pi R^3 \] where \( R \) is the radius of the sphere. Setting the volumes equal: \[ \frac{32}{3} \pi = \frac{4}{3} \pi R^3 \] ### Step 3: Cancel out common terms We can cancel \( \pi \) and \( \frac{1}{3} \) from both sides: \[ 32 = 4 R^3 \] ### Step 4: Solve for \( R^3 \) Dividing both sides by 4: \[ R^3 = \frac{32}{4} = 8 \] ### Step 5: Find \( R \) Taking the cube root of both sides: \[ R = 8^{1/3} = 2 \text{ cm} \] ### Step 6: Calculate the diameter of the sphere The diameter \( D \) of the sphere is given by: \[ D = 2R \] Substituting the value of \( R \): \[ D = 2 \times 2 = 4 \text{ cm} \] ### Final Answer The diameter of the sphere is \( 4 \) cm. ---
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