9MSD=10VSD
1VSD=0.9mm
1MSD=1mm
∴L.C.=MSDMSD−VSD=11−0.9=0.1
Reading = Main scale reading + L.C. × vernier scale reading
=10+(0.1×8)
=10.8mm
Reading of diameter=10.8mm−0.4mm=10.4mm
radius of the bob=5.2mm
=0.52cm=52×10−2cm
JEE Main 2021 — Physics Mechanics
The diameter of a spherical bob is measured using a vernier callipers. 9 divisions of the main scale, in the vernier callipers, are equal to 10 divisions of vernier scale. One main scale division is 1mm. The main scale reading is 10mm and 8th division of vernier scale was found to coincide exactly with one of the main scale division. If the given vernier callipers has positive zero error of 0.04cm, then the radius of the bob is _____________ ×10−2cm.
Held on 31 Aug 2021 · Verified 6 Jul 2026.
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