Question

A microscope is provided with a main scale graduated with 20divisons in 1cm and a vernier scale with 50divisons on it of length same as of 49 divisions of main scale. Find the least count of the microscope.​

Answer 1

50 divisions of Vernier scale = 49 divisions of main scale

or, 1 division of Vernier scale = 49/50 divisions of main scale

or, 1 division of Vernier scale = 0.98 division of main scale

so, least count of vernier scale = 1 main scale division - 1 vernier scale division

= 1 main scale division - 0.98 main scale division

= 0.02 main scale division.

given, 1 main scale division = 1/20 cm

so, least count of microscope = 0.02 × 1/20 = 0.01/10 = 0.001cm

hence, least count of microscope is 0.001cm

Answer 2

Answer:

Explanation:

50 divisions of Vernier scale = 49 divisions of main scale

or, 1 division of Vernier scale = 49/50 divisions of main scale

or, 1 division of Vernier scale = 0.98 division of main scale

so, least count of vernier scale = 1 main scale division - 1 vernier scale division

= 1 main scale division - 0.98 main scale division

= 0.02 main scale division.

given, 1 main scale division = 1/20 cm

so, least count of microscope = 0.02 × 1/20 = 0.01/10 = 0.001cm

Hence, least count of microscope is 0.001cm