Positive zero error =0.2mm
Main scale reading =8.5cm
Vernier scale reading=6×0.01=0.06cm
Final reading=8.5+0.06−0.02=8.54cm
JEE Main 2021 — Physics Mechanics
The vernier scale used for measurement has a positive zero error of 0.2mm. If while taking a measurement it was noted that 0 on the vernier scale lies between 8.5cm and 8.6cm. Vernier coincidence is 6, then the correct value of measurement is cm.
(least count=0.01cm)
Held on 17 Mar 2021 · Verified 6 Jul 2026.
8.36cm
8.54cm
8.58cm
8.56cm
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