Ina vernier callipers $$N$$ division of vernier coincide with $$\left( {N - 1} \right)$$ divisions of main scale in which length of a division is $$1\,mm.$$ The least count of the instrument in $$cm$$ is
A.
$$N$$
B.
$$N - 1$$
C.
$$\frac{1}{{10\,N}}$$
D.
$$\left( {\frac{1}{N}} \right) - 1$$
Answer :
$$\frac{1}{{10\,N}}$$
Solution :
$$\eqalign{
& L.C = \frac{{{\text{value of 1 division of main scale}}}}{{{\text{number of division on main scale}}}} \cr
& = \frac{1}{N}mm = \frac{1}{{10\,N}}cm \cr} $$
Releted MCQ Question on Basic Physics >> Unit and Measurement
Releted Question 1
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