Question

A student took the least count of a vernier calliper as 0.01 mm instead of 0.01 cm and found that the length of a copper rod was 4.909 cm. If one M.S.D. = 1 mm, then find
(1) the main scale reading
(2) the vernier coinciding division
(3) the correct length of the rod

Answer 1

(i) The value of 1 M.S.D. = 1mm (given)
the correct least count of vernier calliper is 0.01 cm.
Then what is the formula of the least count
`(L.C=(1 M.S.D.)/(N))`
How many divisions are present on the vernier scale?
The formula for the length of a vernier calipers is l
=` M.S.R. + V.C. xx L.C.---(1)`
Is the value measured by the student a mistake?
what is its value?
Then,the value of MSR is =4.9 cm.
Then,what is the value of V.C.D.?
rArr By inserting the value of M.S.R., V.C.D. and L.C. in (1) the correct length of the rod is obtained.
(ii) M.S.R. = 49 mm, V.C.D. = 9, Original reading = 49.9 mm