Question

On a vernier calliper, 25 vernier scale divisions are equal in length to 24 main scale divisions. One main scale division is 1 mm. Find the least count of the instrument.

Options

• 0.04 mm

• 0.01 mm

• 0.02 mm

• 0.08 mm

Answer 1

0.04 mm

Explanation:

Least count = 1 MSD -1 VSD

25 VSD = 24 MSD

Here 1 MSD = 1 mm

Now, least count = 1 MSD - \[\frac {24}{25}\]MSD

= \[\frac{25\mathrm{~MSD}-24\mathrm{~MSD}}{25}\] = \[\frac {1\text{MSD}}{25}\] = \[\frac {\text {1 mm}}{25}\] = 0.4 mm