B Can I use the circle circumference formula for a sphere?

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The discussion clarifies that the circumference formula for a circle can indeed be applied to a sphere, specifically for calculating the circumference of a great circle. The user inquired about the correctness of their calculation, which yielded a circumference of 19.4 inches for a sphere with a radius of 3.09 inches. The response confirmed that this is accurate, as the formula for circumference remains consistent across both shapes. The key takeaway is that the circumference of a sphere is derived from its great circle, which is the largest circle that can be drawn on the sphere's surface. Understanding this concept simplifies the calculation process for spheres.
Perchaddition
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Trying to calculate a circumference of a sphere from a radius of 3.09 inches. Is 19.4 a correct answer? Just ran numbers in the first circumference calculator I found http://calcurator.org/circumference-calculator/. Can I use the same formula for a sphere? What can I say ...Geometry is not my passion
 
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Perchaddition said:
Trying to calculate a circumference of a sphere from a radius of 3.09 inches. Is 19.4 a correct answer?
Yes.
Perchaddition said:
Just ran numbers in the first circumference calculator I found http://calcurator.org/circumference-calculator/. Can I use the same formula for a sphere? What can I say ...Geometry is not my passion
The circumference is always that of a circle. In the case of a sphere, it is the circumference of a great circle, circles of maximal circumference.
 
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Define circumference of a sphere.
 
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fresh_42 said:
Yes.

The circumference is always that of a circle. In the case of a sphere, it is the circumference of a great circle, circles of maximal circumference.
Thank you. Appreciate your explanation.
 
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