Physical World Units And Measurements Ques 42

42. If the error in the measurement of radius of a sphere is $2 \%$, then the error in the determination of volume of the sphere will be:

[2008]

(a) $4 \%$

(b) $6 \%$

(c) $8 \%$

(d) $2 \%$

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Answer:

Correct Answer: 42.(b)

Solution:

  1. (b) Given, error in the measurement of radius

of a sphere $\frac{\Delta r}{r} \times 100=2 \%$

Volume of the sphere $V=\frac{4}{3} \pi r^{3}$

$\therefore$ Error in the volume $\frac{\Delta V}{V} \times 100$

$= \pm 3 \cdot \frac{\Delta r}{r} \times 100=3 \times 2 \%= \pm 6 \%$