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Question
Solve the numerical example.
The diameter of a sphere is 2.14 cm. Calculate the volume of the sphere to the correct number of significant figures.
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Solution
Volume of sphere =`4/3 pi"r"^3`
`= 4/3 xx 3.142 xx (2.14/2)^3` ...`(because "r" = "d"/2)`
`= 4/3 xx 3.142 xx (1.07)^3`
= 1.333 × 3.142 × (1.07)3
= {antilog [log (1.333) + log(3.142) + 3 log(1.07)]}
= {antilog [0.1249 + 0.4972 + 3 (0.0294)]}
= {antilog [0.1249 + 0.4972 + 3 (0.0294)]}
= {antilog [0.6221 + 0.0882]}
= {antilog [0.7103]}
= 5.133cm3
In multiplication or division, the final result should retain as many significant figures as there are in the original number with the least significant figures.
∴ Volume in correct significant figures = 5.13 cm3
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