One main scale division of a vernier callipers is $a$ $cm$ and $n ^{\text {th }}$ division of the vernier scale coincide with $( n -1)^{\text {th }}$ division of the main scale. The least count of the callipers in $mm$ is

The vernier constant of Vernier callipers is $0.1 \,mm$ and it has zero error of $(-0.05) \,cm$. While measuring diameter of a sphere, the main scale reading is $1.7 \,cm$ and coinciding vernier division is $5$. The corrected diameter will be ……….. $\times 10^{-2} \,cm$

The vernier scale of a travelling microscope has $50$ divisions which coincide with $49$ main scale divisions. If each main scale division is $0.5\, mm$, calculate the minimum inaccuracy in the measurement of distance.

A vernier callipers has $20$ divisions on the vernier scale, which coincides with $19^{\text {th }}$ division on the main scale. The least count of the instrument is $0.1 \mathrm{~mm}$. One main scale division is equal to $. . .  . . ..$ $\mathrm{mm}$

A screw gauge gives the following readings when used to measure the diameter of a wire

Main scale reading : $0 \,\mathrm{~mm}$

Circular scale reading $: 52$ $divisions$

Given that $1\, \mathrm{~mm}$ on main scale corresponds to $100\, divisions$ on the circular scale. The diameter of the wire from the above data is …… $cm$