Least count of a travelling microscope
One main scale division is 0.05 cm and the vernier has 50 divisions, so the least count is 0.001 cm.
Least count
0.001cm
0.05 cm / 50 = 0.001 cm
Least count = 1 main scale division / number of vernier divisions.
Least count = 1 main scale division / number of vernier divisions
A travelling microscope is used for small displacements, such as the height of a liquid column or the diameter of a capillary. The working for the textbook numbers is 0.05 cm / 50 = 0.001 cm.
Other instruments
Travelling microscope: quick answers
What is the least count of a travelling microscope?
One main scale division is 0.05 cm and the vernier has 50 divisions, so the least count is 0.001 cm. Least count = 1 main scale division / number of vernier divisions.
How do I find the least count of my travelling microscope?
Least count = 1 main scale division / number of vernier divisions. For the instrument in front of you, read the scale and use your own numbers in the tool above.
Why does the least count matter?
The least count is the smallest reading you can make, so it sets the smallest error in a single measurement. Travelling microscope measures small displacements, such as the height of a liquid column or the diameter of a capillary.