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Units And Measurement

Question
CBSEENPH11020741

If the error in the measurement of radius of sphere is 2%, then the error in the determination of volume of the sphere will be

  • 4%

  • 6%

  • 8%

  • 2%

Solution

B.

6%

Volume space of space straight a space sphere space equals space 4 over 3 straight pi space left parenthesis radius right parenthesis cubed
or space straight V space equals space 4 over 3 πR cubed
Taking space logarithium space on space both space sides comma space we space have space
log space straight V space equals space log space 4 over 3 space πR cubed
Taking space logarithium space on space both space sides comma space we space have
log space straight V space equals space log space 4 over 3 straight pi space plus 3 space log space straight R
Differentiating comma space we space get comma
fraction numerator increment straight V over denominator straight V end fraction space equals space 0 space plus fraction numerator 3 increment straight R over denominator straight R end fraction
Accordingly comma space fraction numerator increment straight R over denominator straight R end fraction space equals 2 percent sign
Thus comma space fraction numerator increment straight V over denominator straight V end fraction space equals space 3 space straight x space 2 percent sign space equals space 6 percent sign