In orthogonal turning, the chip formation is influenced by several factors, including the feed rate and the cutting edge angle. The width of the chip is one of the important parameters to understand, as it relates directly to the feed rate and the geometry of the cutting process.
The formula for calculating the width of the chip in an orthogonal cutting process is given by:
\[
{Width of the chip} = {feed} = 0.1 \, {mm/rev}
\]
In this case, the side cutting edge angle is given as \(0^\circ\) (which is a special case where the cutting edge is essentially perpendicular to the surface being cut). Since the cutting edge angle is \( 0^\circ \), the width of the chip is simply equal to the feed rate. Thus, the width of the chip is:
\[
{Width of the chip} = 0.5 \, {mm}
\]
Therefore, the correct answer is 0.5 mm.