If \( 50 \) Vernier divisions are equal to \( 49 \) main scale division of a traveling microscope and one smallest reading of main scale is \( 0.5 \, \text{mm} \), the Vernier constant of traveling microscope is:
\( 0.1 \, \text{mm} \)
\( 0.1 \, \text{cm} \)
\( 0.01 \, \text{cm} \)
\( 0.01 \, \text{mm} \)
