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What, roughly, is the percent uncertainty in the volume of a spherical beach ball whose radius is r = 2.86 plus or minus .09 m?

User HamSh
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1 Answer

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The volume of a sphere is calculated through the equation,

V = 4πr³ /3
where r is the radius of the given.

If the radius is 2.86, we can substitute the value to the equation above such that,
V = 4π(2.86)³ / 3 = 97.99π m³

When the radius is 0.09 m plus the given radius then,
V = 4π(2.86 - 0.09)³ / 3 = 89.03π m³

The difference between the volumes is equal to,
difference = 97.99π - 89.03π m³ = 8.96π m³

Dividing this to the original volume and multiplying by 100%,
percentage = (8.96π/97.99π) x 100%
percentage = 9.14%.

Hence, the expected percent uncertainty is equal to 9.14%.
User Fmucar
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