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Determine a volume and the diameter of a 12.5kg gold sphere?

GROUPS:

A standard gold bar weighs 12.5kg. The density of gold is 19.3g/cm^3. What is the diameter of a sphere made from the same gold bar? I have tried various versions of the question in WolframAlpha. WA will happily understand and return the diameter of a sphere of a certain volume. Is there a way to get it to return the answer in one question?

POSTED BY: Simon Allen
Answer
3 months ago

first calculate the volume from the mass and the density, then calculate the diameter of the sphere from the volume.

POSTED BY: Frank Kampas
Answer
3 months ago

Yes that would work. I have no issue with doing this on paper even by hand without a calculator! If I type in Wolfram Alpha "diameter of sphere of volume 10" it will not only understand the question and interpret it but also return the answer.

If I type "Volume of a sphere of volume of a gold bar" it fails. As does "Volume of a sphere of volume of a solid of 12.5 kg and a density of 19.3g/cm^3"

Can I get it to solve the problem in one pass?

POSTED BY: Simon Allen
Answer
3 months ago

Perhaps

solve 4/3 pi r^3=12.5 kg/19.3 g/cm^3 for r

WolframAlpha link

I tried to get it to understand something like

weight=12.5 kg, density=19.3g/cm^3, volume=weight/density, solve 3/4 pi r^3=volume for r

but had no success

POSTED BY: Bill Simpson
Answer
3 months ago

Solve[(4 Pi/3)* r^3 == m*d, r]

POSTED BY: Updating Name
Answer
3 months ago

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