The diameter of a flywheel is increased by 1% . Increase in its moment of interia about the central axis is

Options

A. `1 %`
B. `4%`
C. `3%`
D. `2%`

Explanation

`I = = MR ^(2)`
taking log both side
`log l = log M + 2 log R`
Differentiate it, we get
`(dl)/(I) = 0 + 2 (dR)/(R)`
`(dl)/(I) = 2 (d R)/(R)`
`therefore (dl xx 100)/( I ) = 2 xx (dR)/(R) xx 100`
`implies %` increasec ` = 2 xx 1 % = 2 %`