Question

if the error in the measurement if diameter of a circular disc is 1% then the error in the measurement of its surface area will be??​

Answer 1

Answer:

Ans is 2%

Explanation:

as we know total surface area=2×pie×r^2

I.e)2×pie×(D/2)^2

now apply log

log A=log(pie/2) + 2log D

now differentiate w.r.t dD

(dA/dD)×1/A=2/D

now rearranging we get

dA/A=2dD/D

so change=1×2=2%