Explain the factors affecting the extent of inductive effect.

(N/A) The inductive effect ($I$-effect) is a permanent displacement of shared electron pairs along a carbon chain due to the difference in electronegativity between atoms or groups. The factors affecting its extent are:
$1$. Electronegativity difference: The magnitude of the $I$-effect depends on the difference in electronegativity between the substituent and the carbon atom. $A$ larger difference leads to a stronger $I$-effect.
$2$. Distance: The $I$-effect is a distance-dependent phenomenon. It decreases rapidly as the distance from the substituent increases and becomes negligible after the third carbon atom.
$3$. Nature of the substituent: The nature of the group (electron-withdrawing $-I$ or electron-donating $+I$) determines the direction of the electron displacement. The strength of the effect depends on the specific group attached (e.g.,$-NO_2$ has a stronger $-I$ effect than $-F$).