Quandaries and Queries


I was in class today and I learned how to calculate the volume of a sphere. I understood it easily but can't find the logic behind it. So here are my questions, in the formula why is the radius cubic and not squared? And what does 4/3 have to do with it?

Thanks alot, Mike


Hi Mike,

Volumes are measured in cubic units; cubic centimeters, cubic inches, cubic meters etc. Think of a box with its dimensiions measured in centimeters. To find its volume you need the multiply the length, width and height, three measurement that are all in centimeters, so the volume is in centimeters cubed. For a sphere the volume is also in cubic units but the only dimension is the radius so we should expect that there is a "radius cubed" factor in the volume expression.

"What does 4/3 have to do with it?" is a harder question to answer. Have a look at Walters answer to this question and Harley's answer to this question and see if they help.



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