Circumference

speedy

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If Earth is a perfect sphere of 4,000 miles radius what is it's circumference in miles?
 

Dr.Peterson

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Since Earth is not a perfect sphere of 4000 miles radius, I could logically say anything I want and my statement would be "true"; but that wouldn't be what you're asking. You mean, "If Earth were a perfect sphere of 4,000 miles radius what would be its circumference in miles?"

Do you know the formula for the circumference of a circle? It's \(\displaystyle C = 2\pi r\).

Replace \(\displaystyle r\) with 4000, and do the calculation.
 
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Subhotosh Khan

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If Earth is a perfect sphere of 4,000 miles radius what is it's circumference in miles?
Circumference of a sphere is defined as the circumference of the great circle around the sphere

Circumference C = 2 * \(\displaystyle \pi \) * radius

Continue....
 

speedy

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Dec 26, 2019
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Since Earth is not a perfect sphere of 4000 miles radius, I could logically say anything I want and my statement would be "true"; but that wouldn't be what you're asking. You mean, "If Earth were a perfect sphere of 4,000 miles radius what would be its circumference in miles?"

Do you know the formula for the circumference of a circle? It's \(\displaystyle C = 2\pi r\).

Replace \(\displaystyle r\) with 4000, and do the calculation.
Have i worked it out correct = 25132.74 miles
 

Jomo

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Have i worked it out correct = 25132.74 miles
I don't know as you never said what the circumference equals. Please give complete answers.
 

Levido

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Dec 22, 2019
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Have i worked it out correct = 25132.74 miles
Yes, 25132.74 is the correct answer to 2 decimal places for the calculation 2*pi*4000 (in miles)
 

toponlinetool

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Jan 7, 2020
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Formula for sphere can be calculated as 2*pi*r
Here r= 4000 miles,
Circumference= 25132.74 miles
Above mentioned answers are correct.
 
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