Least count = No of divisions on vernier scale value of main scale division =301MSD=301×21∘=601∘=1 minute
JEE Main 2009 — Physics Mechanics
In an experiment the angles are required to be measured using an instrument. 29 divisions of the main scale exactly coincide with the 30 divisions of the vernier scale. If the smallest division of the main scale is half-a-degree (=0.5∘), then the least count of the instrument is
Held on 30 Apr 2009 · Verified 6 Jul 2026.
one minute
half minute
one degree
half degree
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